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1.  Management of suspected infectious diarrhoea by English GPs: are they right? 
Background
The criteria used when GPs submit stool specimens for microbiological investigation are unknown.
Aim
To determine what criteria GPs use to send stool specimens, and if they are consistent with national guidance, and whether GPs would prescribe an antibiotic before they receive a result.
Design and setting
Questionnaire survey of 974 GPs in 172 surgeries in England.
Method
GPs were sent a questionnaire (23 questions) based on national guidance.
Results
Questionnaires were returned by 90% (154/172) of surgeries and 49% (477/968) of GPs. GPs reported sending stool specimens in about 50% of cases of suspected infectious diarrhoea, most commonly because of individual symptoms, rather than public health implications. Fewer considered sampling with antibiotic-associated diarrhoea post hospitalisation, or children with acute, painful, bloody diarrhoea; only 14% mentioned outbreaks as a reason. Nearly one-half of GPs reported they would consider antibiotics in suspected cases of Escherichia coli O157, which is contraindicated. Only 23% of GPs would send the recommended three specimens for ova, cysts, and parasites (OCP) examination. Although 89% of GPs gave some verbal advice on how to collect stool specimens, only 2% of GPs gave patients any written instructions.
Conclusion
GPs need more education to address gaps in knowledge about the risks and diagnosis of different infections in suspected infectious diarrhoea, especially Clostridium difficile post-antibiotics, E. coli O157, and requesting OCPs. Advice on reports, tick boxes, or links to guidance on electronic request forms may facilitate this.
doi:10.3399/bjgp14X676429
PMCID: PMC3876145  PMID: 24567579
antibiotics; diarrhoea; E. coli O157; general practice; guidance; investigation
2.  Risk Factors for Death among Children Less than 5 Years Old Hospitalized with Diarrhea in Rural Western Kenya, 2005–2007: A Cohort Study 
PLoS Medicine  2012;9(7):e1001256.
A hospital-based surveillance study conducted by Ciara O'Reilly and colleagues describes the risk factors for death amongst children who have been hospitalized with diarrhea in rural Kenya.
Background
Diarrhea is a leading cause of childhood morbidity and mortality in sub-Saharan Africa. Data on risk factors for mortality are limited. We conducted hospital-based surveillance to characterize the etiology of diarrhea and identify risk factors for death among children hospitalized with diarrhea in rural western Kenya.
Methods and Findings
We enrolled all children <5 years old, hospitalized with diarrhea (≥3 loose stools in 24 hours) at two district hospitals in Nyanza Province, western Kenya. Clinical and demographic information was collected. Stool specimens were tested for bacterial and viral pathogens. Bivariate and multivariable logistic regression analyses were carried out to identify risk factors for death. From May 23, 2005 to May 22, 2007, 1,146 children <5 years old were enrolled; 107 (9%) children died during hospitalization. Nontyphoidal Salmonella were identified in 10% (118), Campylobacter in 5% (57), and Shigella in 4% (42) of 1,137 stool samples; rotavirus was detected in 19% (196) of 1,021 stool samples. Among stools from children who died, nontyphoidal Salmonella were detected in 22%, Shigella in 11%, rotavirus in 9%, Campylobacter in 5%, and S. Typhi in <1%. In multivariable analysis, infants who died were more likely to have nontyphoidal Salmonella (adjusted odds ratio [aOR] = 6·8; 95% CI 3·1–14·9), and children <5 years to have Shigella (aOR = 5·5; 95% CI 2·2–14·0) identified than children who survived. Children who died were less likely to be infected with rotavirus (OR = 0·4; 95% CI 0·2–0·8). Further risk factors for death included being malnourished (aOR = 4·2; 95% CI 2·1–8·7); having oral thrush on physical exam (aOR = 2·3; 95% CI 1·4–3·8); having previously sought care at a hospital for the illness (aOR = 2·2; 95% CI 1·2–3·8); and being dehydrated as diagnosed at discharge/death (aOR = 2·5; 95% CI 1·5–4·1). A clinical diagnosis of malaria, and malaria parasites seen on blood smear, were not associated with increased risk of death. This study only captured in-hospital childhood deaths, and likely missed a substantial number of additional deaths that occurred at home.
Conclusion
Nontyphoidal Salmonella and Shigella are associated with mortality among rural Kenyan children with diarrhea who access a hospital. Improved prevention and treatment of diarrheal disease is necessary. Enhanced surveillance and simplified laboratory diagnostics in Africa may assist clinicians in appropriately treating potentially fatal diarrheal illness.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Diarrhea—passing three or more loose or liquid stools per day—kills about 1.5 million young children every year, mainly in low- and middle-income countries. Globally, it is the second leading cause of death in under-5-year olds, causing nearly one in five child deaths. Diarrhea, which can lead to life-threatening dehydration, is a common symptom of gastrointestinal infections. The pathogens (viruses, bacteria, and parasites) that cause diarrhea spread through contaminated food or drinking water, and from person to person through poor hygiene and inadequate sanitation (unsafe disposal of human excreta). Interventions that prevent diarrhea include improvements in water supplies, sanitation and hygiene, the promotion of breast feeding, and vaccination against rotavirus (a major viral cause of diarrhea). Treatments for diarrhea include oral rehydration salts, which prevent and treat dehydration, zinc supplementation, which decreases the severity and duration of diarrhea, and the use of appropriate antibiotics when indicated for severe bacterial diarrhea.
Why Was This Study Done?
Nearly half of deaths from diarrhea among young children occur in Africa where diarrhea is the single largest cause of death among under 5-year-olds and a major cause of childhood illness. Unfortunately, although some of the risk factors for death from diarrhea in children in sub-Saharan Africa have been identified (for example, having other illnesses, poor nutrition, and not being breastfed), little is known about the relative contributions of different diarrhea-causing pathogens to diarrheal deaths. Clinicians need to know which of these pathogens are most likely to cause death in children so that they can manage their patients appropriately. In this cohort study, the researchers characterize the causes and risk factors associated with death among young children hospitalized for diarrhea in Nyanza Province, western Kenya, an area where most households have no access to safe drinking water and a quarter lack latrines. In a cohort study, a group of people with a specific condition is observed to identify which factors lead to different outcomes.
What Did the Researchers Do and Find?
The researchers enrolled all the children under 5 years old who were hospitalized over a two-year period for diarrhea at two district hospitals in Nyanza Province, tested their stool samples for diarrhea-causing viral and bacterial pathogens, and recorded which patients died in-hospital. They then used multivariable regression analysis (a statistical method) to determine which risk factors and diarrheal pathogens were associated with death among the children. During the study, 1,146 children were hospitalized, 107 of whom died in the hospital. 10% of all the stool samples contained nontyphoidal Salmonella, 4% contained Shigella (two types of diarrhea-causing bacteria), and 19% contained rotavirus. By contrast, 22% of the samples taken from children who died contained nontyphoidal Salmonella, 11% contained Shigella, 9% contained rotavirus, and 5% contained Campylobacter (another bacterial pathogen that causes diarrhea). Compared to survivors, infants (children under 1 year of age) who died were nearly seven times more likely to have nontyphoidal Salmonella in their stools and children under 5 years old who died were five and half times more likely to have Shigella in their stools but less likely to have rotavirus in their stools. Other factors associated with death included being malnourished, having oral thrush (a fungal infection of the mouth), having previously sought hospital care for diarrhea, and being dehydrated.
What Do These Findings Mean?
These findings indicate that, among young children admitted to the hospital in western Kenya with diarrhea, infections with nontyphoidal Salmonella and with Shigella (but not with rotavirus) were associated with an increased risk of death. Because this study only captured deaths in hospital and most diarrheal deaths in developing countries occur at home, these results may not accurately reflect the pathogens associated with overall childhood diarrheal deaths. In addition, they may not be generalizable to other geographical regions. Nevertheless, given that that there are currently no vaccines available for most bacterial diarrheal diseases, these findings highlight the importance of Kenya and other developing countries implementing effective strategies for the prevention and management of diarrheal diseases in children such as increasing access to improved water, sanitation, and hygiene, and community-level promotion of the use of oral rehydration solution and zinc supplements. They also suggest that enhanced surveillance and simplified laboratory diagnostics for diarrheal pathogens could help clinicians identify those children presenting to hospital with diarrhea who are at high risk of death and prioritize their treatment.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001256.
The World Health Organization provides information on diarrhea (in several languages); its 2009 report with UNICEF Diarrhea: why children are still dying and what can be done, which includes the WHO/UNICEF recommendations for the treatment and prevention of diarrhea in children, can be downloaded from the Internet
The children's charity UNICEF, which protects the rights of children and young people around the world, provides information on diarrhea (in several languages)
doi:10.1371/journal.pmed.1001256
PMCID: PMC3389023  PMID: 22802736
3.  Patients’ perspectives on providing a stool sample to their GP: a qualitative study 
The British Journal of General Practice  2014;64(628):e684-e693.
Background
Stool specimen collection is challenging and informal feedback has indicated that participants find the process difficult. Increasing stool specimen returns would improve the investigation of outbreaks of diarrhoeal and food-borne disease.
Aim
To explore the barriers to stool sample collection and specimen return to ascertain which factors may help to improve the process.
Design and setting
Qualitative patient interview study in Gloucester, UK.
Method
A two-stage purposive sampling process was used to identify patients who had either previous experience or no experience of collecting a stool sample. The interview schedule, based on the theory of planned behaviour, was used to facilitate interviews with 26 patients. Interview transcripts were analysed using a modified framework analysis.
Results
Barriers to collection included embarrassment, fear of results, concerns around hygiene and contamination, discretion and privacy, and lack of information. Personal gain was identified as the main incentive to collecting and returning a stool sample. The need for an information leaflet on stool collection was emphasised by most patients.
Conclusions
GPs could make a number of small changes that could make a big difference for patients and potentially increase stool sample return. If they, rather than receptionists, distributed collection kits it may be easier for patients to ask any questions they had regarding collection. In addition, the provision of a stool-collection information leaflet could increase patients’ confidence regarding collecting the sample, and providing drop-off boxes for specimens could help prevent patients’ embarrassment regarding handing their stool over to a receptionist.
doi:10.3399/bjgp14X682261
PMCID: PMC4220220  PMID: 25348992
information leaflet; opinion; patient interview; primary care; qualitative; stool collection
4.  Characterisation of Clostridium difficile Hospital Ward–Based Transmission Using Extensive Epidemiological Data and Molecular Typing 
PLoS Medicine  2012;9(2):e1001172.
A population-based study in Oxfordshire (UK) hospitals by Sarah Walker and colleagues finds that in an endemic setting with good infection control, ward-based contact cannot account for most new cases of Clostridium difficile infection.
Background
Clostridium difficile infection (CDI) is a leading cause of antibiotic-associated diarrhoea and is endemic in hospitals, hindering the identification of sources and routes of transmission based on shared time and space alone. This may compromise rational control despite costly prevention strategies. This study aimed to investigate ward-based transmission of C. difficile, by subdividing outbreaks into distinct lineages defined by multi-locus sequence typing (MLST).
Methods and Findings
All C. difficile toxin enzyme-immunoassay-positive and culture-positive samples over 2.5 y from a geographically defined population of ∼600,000 persons underwent MLST. Sequence types (STs) were combined with admission and ward movement data from an integrated comprehensive healthcare system incorporating three hospitals (1,700 beds) providing all acute care for the defined geographical population. Networks of cases and potential transmission events were constructed for each ST. Potential infection sources for each case and transmission timescales were defined by prior ward-based contact with other cases sharing the same ST. From 1 September 2007 to 31 March 2010, there were means of 102 tests and 9.4 CDIs per 10,000 overnight stays in inpatients, and 238 tests and 15.7 CDIs per month in outpatients/primary care. In total, 1,276 C. difficile isolates of 69 STs were studied. From MLST, no more than 25% of cases could be linked to a potential ward-based inpatient source, ranging from 37% in renal/transplant, 29% in haematology/oncology, and 28% in acute/elderly medicine to 6% in specialist surgery. Most of the putative transmissions identified occurred shortly (≤1 wk) after the onset of symptoms (141/218, 65%), with few >8 wk (21/218, 10%). Most incubation periods were ≤4 wk (132/218, 61%), with few >12 wk (28/218, 13%). Allowing for persistent ward contamination following ward discharge of a CDI case did not increase the proportion of linked cases after allowing for random meeting of matched controls.
Conclusions
In an endemic setting with well-implemented infection control measures, ward-based contact with symptomatic enzyme-immunoassay-positive patients cannot account for most new CDI cases.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Hospital-acquired infections are common and occur when patients are infected with an organism found in the hospital or health-care environment. Hospital-acquired infections can sometimes cause no symptoms but often lead to illness or even death. A leading hospital-acquired infection is with the anaerobic bacterium Clostridium difficile, which causes gastrointestinal problems, including diarrhea, leading to severe illness and even death, especially in older patients or patients who are already seriously ill. Between 7% and 26% of elderly adult inpatients in hospitals may be asymptomatic carriers of C. difficile, and the spores that are formed by this organism can live outside of the human body for long periods of time and are notoriously resistant to most routine surface-cleaning methods. Following major hospital-associated outbreaks around the world, C. difficile infection has become a prime target for expensive prevention and infection control strategies.
Why Was This Study Done?
Prevention strategies and infection control measures have contributed to reducing the incidence of C. difficile infection, however, to date, there have not been any robust evaluations of the impact of such strategies in reducing the spread of infection at the individual level. In order to implement improved, cost-effective policies, and to work out how to reduce incidence even further, a better understanding of person-to-person spread is crucial, especially as infection with C. difficile depends on a combination of factors, such as antibiotic exposure and host susceptibility. Therefore, the researchers conducted this study to examine in detail the transmission of C. difficile in hospital wards in order to give more insight and information on the nature of person-to-person spread.
What Did the Researchers Do and Find?
The researchers used a population-based study in Oxfordshire, UK, to investigate hospital ward–based transmission of defined C. difficile strains from symptomatic patients by identifying C. difficile infection from routine clinical microbiological samples from 1 September 2007 to 31 March 2010. Throughout this period, Oxfordshire hospitals operated a rigorous infection control policy monitored by infection control staff, in which stool samples for C. difficile testing were taken from admitted patients with persistent diarrhea, and from patients with any diarrhea who were 65 years or older. The researchers tested all stool samples for C. difficile toxins by enzyme immunoassay, cultured positive samples, and genotyped C. difficile isolates by using multi-locus sequence typing (to identify strains, that is, sequence types), and finally, constructed networks of cases and potential transmissions (by tracing contacts for up to 26 weeks) for each sequence type identified.
In order to show which ward-based contacts potentially incorporated direct person-to-person spread and indirect transmission via the environment during shared ward exposure, the researchers analysed links (ward contacts) between the first case (the donor) and the second case (the recipient) for all pairs of cases with the same sequence type. The researchers then calculated the minimum infectious period by measuring the time between the first infected stool sample from the donor and ward contact with the recipient, and calculated the incubation period as the time between this ward contact and the first infected stool sample in the recipient. To reduce the possibility of shared ward contacts occurring by chance, the researchers used patients with negative enzyme immunoassay stool samples as controls to estimate how often such ward contacts reflected actual transmission rather than chance.
Over the study period, almost 30,000 stool samples from almost 15,000 patients were tested for C. difficile, with 4.4% (1,282) found positive for C. difficile in enzyme immunoassay and culture. With genotyping, the researchers identified 69 strains (sequence types) of C. difficile. The researchers found that the majority (66%) of cases of C. difficile infection were not linked to known cases, and only 23% had a credible ward-based donor sharing the same sequence type of C. difficile. Furthermore, the researchers found that most probable transmissions occurred less than one week after the onset of symptoms, with a minority (10%) occurring after eight weeks. Most incubation periods were less than four weeks, but a few (13%) were more than 12 weeks. Importantly, even after allowing for the random meeting of matched controls and for persistent ward contamination, the proportion of linked cases did not increase following ward discharge of a C. difficile infection case.
What Do These Findings Mean?
These findings show that in an endemic setting with well-implemented infection control measures, ward-based contact with symptomatic, enzyme-immunoassay-positive patients cannot account for most new cases of C. difficile infection. Crucially, these findings mean that C. difficile infection might not be effectively controlled by current strategies to prevent person-to-person spread. Although the researchers were able to distinguish different strains of C. difficile, there were insufficient numbers of these different strains to deduce whether the results they obtained might be different if there was a different combination of strain types, that is, if some strains were spreading more in hospitals than others. Finally, in order to determine what other types of control interventions are required to reduce the spread of C. difficile, a better understanding of other routes of transmission and reservoirs of infectivity is needed.
Additional Information
Please access these web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001172.
This study is further discussed in a PLoS Medicine Perspective by Stephan Harbarth and Matthew Samore
The US Centers for Disease Control and Prevention provides information about C. difficile infection, as does the UK Health Protection Agency
The World Health Organization has published a guide for preventing hospital-acquired infections
doi:10.1371/journal.pmed.1001172
PMCID: PMC3274560  PMID: 22346738
5.  A Multicentre Study of Shigella Diarrhoea in Six Asian Countries: Disease Burden, Clinical Manifestations, and Microbiology 
PLoS Medicine  2006;3(9):e353.
Background
The burden of shigellosis is greatest in resource-poor countries. Although this diarrheal disease has been thought to cause considerable morbidity and mortality in excess of 1,000,000 deaths globally per year, little recent data are available to guide intervention strategies in Asia. We conducted a prospective, population-based study in six Asian countries to gain a better understanding of the current disease burden, clinical manifestations, and microbiology of shigellosis in Asia.
Methods and Findings
Over 600,000 persons of all ages residing in Bangladesh, China, Pakistan, Indonesia, Vietnam, and Thailand were included in the surveillance. Shigella was isolated from 2,927 (5%) of 56,958 diarrhoea episodes detected between 2000 and 2004. The overall incidence of treated shigellosis was 2.1 episodes per 1,000 residents per year in all ages and 13.2/1,000/y in children under 60 months old. Shigellosis incidence increased after age 40 years. S. flexneri was the most frequently isolated Shigella species (1,976/2,927 [68%]) in all sites except in Thailand, where S. sonnei was most frequently detected (124/146 [85%]). S. flexneri serotypes were highly heterogeneous in their distribution from site to site, and even from year to year. PCR detected ipaH, the gene encoding invasion plasmid antigen H in 33% of a sample of culture-negative stool specimens. The majority of S. flexneri isolates in each site were resistant to amoxicillin and cotrimoxazole. Ciprofloxacin-resistant S. flexneri isolates were identified in China (18/305 [6%]), Pakistan (8/242 [3%]), and Vietnam (5/282 [2%]).
Conclusions
Shigella appears to be more ubiquitous in Asian impoverished populations than previously thought, and antibiotic-resistant strains of different species and serotypes have emerged. Focusing on prevention of shigellosis could exert an immediate benefit first by substantially reducing the overall diarrhoea burden in the region and second by preventing the spread of panresistant Shigella strains. The heterogeneous distribution of Shigella species and serotypes suggest that multivalent or cross-protective Shigella vaccines will be needed to prevent shigellosis in Asia.
A prospective, population-based study in six Asian countries showed thatShigella appears to be more ubiquitous in Asian impoverished populations than previously thought, and antibiotic-resistant strains have emerged.
Editors' Summary
Background.
Infections that cause diarrhea are a major public health problem in developing countries and other places where resources are scarce, particularly in young children. Although deaths from diarrhea have decreased considerably in recent decades, diarrheal illnesses continue to cause some 2.5 million deaths each year. Shigella, a group of rod-shaped bacteria closely related to those that normally live in the human intestine, is known to cause severe diarrhea in both developed and developing countries, but the global impact of Shigella infection (shigellosis) has not been well characterized. Shigella exists in more than 40 different varieties, an increasing number of cases have been found to be resistant to available antibiotics, and no vaccine is licensed except one oral vaccine in China.
Why Was This Study Done?
The best information available on the impact of shigellosis has been based on historical estimates, which are subject to inaccuracy. More recent studies suggest that the older reports may have underestimated the impact of shigellosis. The authors of this study wanted to obtain more accurate, current estimates of the impact of shigellosis in developing countries.
In addition, immunity to one type of Shigella does not necessarily provide protection against other types. Therefore, in order to develop an effective vaccine, researchers would need to know which types of Shigella are causing illness in affected parts of the world. Accordingly, the authors of this study also wanted to investigate the specific types of Shigella (called “serotypes” because they can be distinguished using serum from immune individuals) involved in cases of diarrhea.
What Did the Researchers Do and Find?
The researchers set up surveillance projects for diarrhea in six developing countries throughout Asia: at three rural or semirural sites (in China, Vietnam, and Thailand) and three urban slum sites (in Bangladesh, Pakistan, and Indonesia). They conducted information campaigns in each area to encourage residents to visit a participating clinic if they or their children developed diarrhea. Patients presenting with diarrhea were enrolled in the study and their medical findings were documented on standardized report forms. Stool or rectal swab specimens were obtained (with patient consent) and sent to laboratories to test for Shigella. When Shigella was identified, the bacteria was serotyped and tested for resistance to antibiotics. Because standard culture methods do not always detect Shigella when it is present, as a double-check, the researchers also tested some of the specimens for a type of DNA (called the ipaH gene) that serves as a molecular “footprint” of Shigella. Patients received treatment according to national guidelines.
The study involved approximately 600,000 participants over 1–3 years, and detected approximately 60,000 cases of diarrhea. Shigella was found in 5% of diarrhea episodes, meaning that two new cases of shigellosis occurred per 1,000 people (of all ages) per year. Rates were higher in children and in people over age 40. Among children less than 5 years old, there were 13 new cases per 1,000 children per year. Rates of shigellosis were higher in the Bangladesh site than in the China, Pakistan, and Indonesia sites, which in turn had higher rates than the Vietnam and Thailand sites.
In contrast to prior studies, no deaths were detected following episodes of shigellosis, and less than one-third of cases of shigellosis were associated with bloody diarrhea (dysentery).
The distribution of serotypes was found to differ from one site to another and within a given site over time. A high percentage of Shigella detected at all sites were resistant to two or more antibiotics. Testing for the ipaH gene was able to identify Shigella in half of patients with bloody diarrhea whose routine stool cultures did not reveal Shigella.
What Do These Findings Mean?
This study found that shigellosis occurs in these Asian sites at a rate approximately 100 times higher than in industrialized countries. The finding that shigellosis frequently occurs in the absence of bloody stool means that government data collections using dysentery as part of the case definition can be expected to miss the majority of shigellosis cases. Also, the increased rate of shigellosis above age 40 shows that older people share significantly in the burden (and most likely the transmission) of shigellosis.
The generally benign clinical course of Shigella-associated diarrhea calls into question the priority that this disease should receive in global vaccine development efforts, especially given the technological challenges posed by the complex and variable distribution of serotypes. Nonetheless, the emergence of multidrug-resistant strains clearly remains a threat, and raises the perennial issue of improved sanitation, rather than new antibiotics, as a long-term solution to the plethora of water-borne illnesses that disproportionately affect developing countries.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.0030353.
World Health Organization topic page on diarrhea
Centers for Disease Control and Prevention: Shigellosis
Wikipedia entry on Shigella (note: Wikipedia is a free Internet encyclopedia that anyone can edit)
doi:10.1371/journal.pmed.0030353
PMCID: PMC1564174  PMID: 16968124
6.  Incidence and Clinical Characteristics of Group A Rotavirus Infections among Children Admitted to Hospital in Kilifi, Kenya  
PLoS Medicine  2008;5(7):e153.
Background
Rotavirus, predominantly of group A, is a major cause of severe diarrhoea worldwide, with the greatest burden falling on young children living in less-developed countries. Vaccines directed against this virus have shown promise in recent trials, and are undergoing effectiveness evaluation in sub-Saharan Africa. In this region limited childhood data are available on the incidence and clinical characteristics of severe group A rotavirus disease. Advocacy for vaccine intervention and interpretation of effectiveness following implementation will benefit from accurate base-line estimates of the incidence and severity of rotavirus paediatric admissions in relevant populations. The study objective was to accurately define the incidence and severity of group A rotavirus disease in a resource-poor setting necessary to make informed decisions on the need for vaccine prevention.
Methods and Findings
Between 2002 and 2004 we conducted prospective surveillance for group A rotavirus infection at Kilifi District Hospital in coastal Kenya. Children < 13 y of age were eligible as “cases” if admitted with diarrhoea, and “controls” if admitted without diarrhoea. We calculated the incidence of hospital admission with group A rotavirus using data from a demographic surveillance study of 220,000 people in Kilifi District. Of 15,347 childhood admissions 3,296 (22%) had diarrhoea, 2,039 were tested for group A rotavirus antigen and, of these, 588 (29%) were positive. 372 (63%) rotavirus-positive cases were infants. Of 620 controls 19 (3.1%, 95% confidence interval [CI] 1.9–4.7) were rotavirus positive. The annual incidence (per 100,000 children) of rotavirus-positive admissions was 1,431 (95% CI 1,275–1,600) in infants and 478 (437–521) in under-5-y-olds, and highest proximal to the hospital. Compared to children with rotavirus-negative diarrhoea, rotavirus-positive cases were less likely to have coexisting illnesses and more likely to have acidosis (46% versus 17%) and severe electrolyte imbalance except hyponatraemia. In-hospital case fatality was 2% among rotavirus-positive and 9% among rotavirus-negative children.
Conclusions
In Kilifi > 2% of children are admitted to hospital with group A rotavirus diarrhoea in the first 5 y of life. This translates into over 28,000 vaccine-preventable hospitalisations per year across Kenya, and is likely to be a considerable underestimate. Group A rotavirus diarrhoea is associated with acute life-threatening metabolic derangement in otherwise healthy children. Although mortality is low in this clinical research setting this may not be generally true in African hospitals lacking rapid and appropriate management.
Combining prospective hospital-based surveillance with demographic data in Kilifi, Kenya, James Nokes and colleagues assess the burden of rotavirus diarrhea in young children.
Editors' Summary
Background.
Rotavirus is a leading global cause of diarrhea in babies and young children. Indeed, most children become infected at least once with this virus before their fifth birthday. Rotavirus is usually spread by children or their caregivers failing to wash their hands properly after going to the toilet and then contaminating food or drink. The symptoms of rotavirus infection—diarrhea, vomiting, and fever—are usually mild, but if the diarrhea is severe it can quickly lead to dehydration. Mild to moderate dehydration can be treated at home by providing the patient with plenty of fluids or with a special rehydration drink that replaces lost water and salts. However, for infants or toddlers who become severely dehydrated, rehydration with intravenous fluids (fluids injected directly into a vein) in hospital may be essential. Unfortunately, in developing countries in sub-Saharan Africa and elsewhere, this treatment is not widely available and every year more than half a million young children die from rotavirus infections.
Why Was This Study Done?
Two rotavirus vaccines that could reduce this burden of disease are currently undergoing clinical trials to determine their effectiveness in sub-Saharan Africa. However, very little is known about the incidence of severe rotavirus infections among children living in this region (that is, how many children develop severe disease every year) or about the clinical characteristics of the disease here. Public-health officials need this baseline information before they can make informed decisions about the mass introduction of rotavirus vaccination and to help them judge whether the intervention has been successful if it is introduced. In this study, the researchers examine the incidence and clinical characteristics of rotavirus infections (specifically, group A rotavirus [GARV] infections; there are several different rotaviruses but GARV causes most human infections) among children admitted to the district hospital in Kilifi, Kenya.
What Did the Researchers Do and Find?
During the 3-year study, more than 15,000 children under the age of 13 years were admitted to Kilifi District Hospital, a little under a quarter of whom had severe diarrhea. Nearly a third of the patients admitted with diarrhea who were tested had a GARV-specific protein in their stools (faeces); by contrast, only three in 100 children admitted without diarrhea showed any evidence of GARV infection. Two-thirds of the GARV-positive children were infants (under 1 year old). Using these figures and health surveillance data (records of births, deaths, and causes of death) collected in the area around the hospital, the researchers calculated that the annual incidence (per 100,000 children) of GARV-positive hospital admissions in the region was 1,431 for infants and 478 for children under age 5 years. Children with GARV-positive diarrhea were less likely to have other illnesses (for example, malnutrition) than those admitted with GARV-negative diarrhea, the researchers report, but were more likely to have life-threatening complications such as severe dehydration and salt imbalances in their blood. However, despite being more ill on admission, only 1 in 50 children with GARV-positive diarrhea died, compared to nearly 1 in 10 of the children with GARV-negative diarrhea; the GARV-positive children also left hospital quicker than those who were GARV-negative.
What Do These Findings Mean?
These findings indicate that severe GARV-positive diarrhea is a major cause of hospital admission among otherwise healthy young children in the Kilifi region of Kenya. By the time they are 5 years old, the researchers estimate that 1 in 50 of the children living in this region will have been admitted to hospital with severe GARV-positive diarrhea. Because rotavirus vaccines prevent virtually all severe rotavirus-associated disease (at least in developed countries where their effectiveness has been extensively tested), the researchers estimate that vaccination might prevent more than 28,000 hospitalizations annually across Kenya; however, this prediction assumes that it is valid to extrapolate from the data obtained from this one district hospital to the entire country.
Additional Information.
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.0050153.
The US Centers for Disease Control and Prevention provides information about rotavirus infections, surveillance, and vaccination (in English and Spanish)
The UK National Health Service Direct health encyclopedia provides information on rotavirus infections
MedlinePlus also provides links to information on rotavirus (in English and Spanish)
The African Rotavirus Surveillance Network is working to improve knowledge about rotavirus infections in Africa
The Rotavirus Vaccine Program aims to reduce child illness and death from diarrhea by increasing the availability of rotavirus vaccines in developing countries (in English and Spanish)
PATH, a nonprofit international organization that aims to create sustainable, culturally relevant solutions to global health problems, also provides detailed information on rotavirus surveillance and disease burden
doi:10.1371/journal.pmed.0050153
PMCID: PMC2488191  PMID: 18651787
7.  Reporting Guidelines for Survey Research: An Analysis of Published Guidance and Reporting Practices 
PLoS Medicine  2011;8(8):e1001069.
Carol Bennett and colleagues review the evidence and find that there is limited guidance and no consensus on the optimal reporting of survey research.
Background
Research needs to be reported transparently so readers can critically assess the strengths and weaknesses of the design, conduct, and analysis of studies. Reporting guidelines have been developed to inform reporting for a variety of study designs. The objective of this study was to identify whether there is a need to develop a reporting guideline for survey research.
Methods and Findings
We conducted a three-part project: (1) a systematic review of the literature (including “Instructions to Authors” from the top five journals of 33 medical specialties and top 15 general and internal medicine journals) to identify guidance for reporting survey research; (2) a systematic review of evidence on the quality of reporting of surveys; and (3) a review of reporting of key quality criteria for survey research in 117 recently published reports of self-administered surveys. Fewer than 7% of medical journals (n = 165) provided guidance to authors on survey research despite a majority having published survey-based studies in recent years. We identified four published checklists for conducting or reporting survey research, none of which were validated. We identified eight previous reviews of survey reporting quality, which focused on issues of non-response and accessibility of questionnaires. Our own review of 117 published survey studies revealed that many items were poorly reported: few studies provided the survey or core questions (35%), reported the validity or reliability of the instrument (19%), defined the response rate (25%), discussed the representativeness of the sample (11%), or identified how missing data were handled (11%).
Conclusions
There is limited guidance and no consensus regarding the optimal reporting of survey research. The majority of key reporting criteria are poorly reported in peer-reviewed survey research articles. Our findings highlight the need for clear and consistent reporting guidelines specific to survey research.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Surveys, or questionnaires, are an essential component of many types of research, including health, and usually gather information by asking a sample of people questions on a specific topic and then generalizing the results to a larger population. Surveys are especially important when addressing topics that are difficult to assess using other approaches and usually rely on self reporting, for example self-reported behaviors, such as eating habits, satisfaction, beliefs, knowledge, attitudes, opinions. However, the methods used in conducting survey research can significantly affect the reliability, validity, and generalizability of study results, and without clear reporting of the methods used in surveys, it is difficult or impossible to assess these characteristics and therefore to have confidence in the findings.
Why Was This Study Done?
This uncertainty in other forms of research has given rise to Reporting Guidelines—evidence-based, validated tools that aim to improve the reporting quality of health research. The STROBE (STrengthening the Reporting of OBservational studies in Epidemiology) Statement includes cross-sectional studies, which often involve surveys. But not all surveys are epidemiological, and STROBE does not include methods' and results' reporting characteristics that are unique to surveys. Therefore, the researchers conducted this study to help determine whether there is a need for a reporting guideline for health survey research.
What Did the Researchers Do and Find?
The researchers identified any previous relevant guidance for survey research, and any evidence on the quality of reporting of survey research, by: reviewing current guidance for reporting survey research in the “Instructions to Authors” of leading medical journals and in published literature; conducting a systematic review of evidence on the quality of reporting of surveys; identifying key quality criteria for the conduct of survey research; and finally, reviewing how these criteria are currently reported by conducting a review of recently published reports of self-administered surveys.
The researchers found that 154 of the 165 journals searched (93.3%) did not provide any guidance on survey reporting, even though the majority (81.8%) have published survey research. Only three of the 11 journals that provided some guidance gave more than one directive or statement. Five papers and one Internet site provided guidance on the reporting of survey research, but none used validated measures or explicit methods for development. The researchers identified eight papers that addressed the quality of reporting of some aspect of survey research: the reporting of response rates; the reporting of non-response analyses in survey research; and the degree to which authors make their survey instrument available to readers. In their review of 117 published survey studies, the researchers found that many items were poorly reported: few studies provided the survey or core questions (35%), reported the validity or reliability of the instrument (19%), discussed the representativeness of the sample (11%), or identified how missing data were handled (11%). Furthermore, (88 [75%]) did not include any information on consent procedures for research participants, and one-third (40 [34%]) of papers did not report whether the study had received research ethics board review.
What Do These Findings Mean?
Overall, these results show that guidance is limited and consensus lacking about the optimal reporting of survey research, and they highlight the need for a well-developed reporting guideline specifically for survey research—possibly an extension of the guideline for observational studies in epidemiology (STROBE)—that will provide the structure to ensure more complete reporting and allow clearer review and interpretation of the results from surveys.
Additional Information
Please access these web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001069.
More than 100 reporting guidelines covering a broad spectrum of research types are indexed on the EQUATOR Networks web site
More information about STROBE is available on the STROBE Statement web site
doi:10.1371/journal.pmed.1001069
PMCID: PMC3149080  PMID: 21829330
8.  A pilot study of infectious intestinal disease in England. 
Epidemiology and Infection  1995;114(2):277-288.
Pilot studies to test methods to determine the incidence, agents, risk factors and socioeconomic costs of infectious intestinal disease (IID) in England were carried out as recommended by the Committee on the Microbiological Safety of Food (the Richmond Committee) by eight general practices. There were case control and enumeration studies of patients presenting to general practice with IID, a population-based prospective cohort study, and a survey of socioeconomic costs of cases of IID. Information on risk factors was obtained by questionnaire (self-administered compared with interview) and a stool sample was requested on all cases and controls. Response rates in the GP case control study were 75% for case questionnaires and 74% for stools; for controls the figures were 70% and 68% respectively. The acceptance rate into the cohort study was 49%; this was significantly higher where phone contact was made. The rate was similar if recruitment was by individual or household. Follow-up of the cohort by negative reporting was complete for up to 6 months. Direct postage by subject was required to obtain fresh stool specimens. Estimates were obtained of presentation rates of IID and the distribution of risk factors which were used to plan the main study. The pilot study demonstrated that it is possible to undertake a national study based in general practice to determine the incidence of IID in the population and presenting to GPs and its agents, risk factors and costs.
PMCID: PMC2271284  PMID: 7705491
9.  Quantitative light microscopic detection of Enterocytozoon bieneusi in stool specimens: a longitudinal study of human immunodeficiency virus-infected microsporidiosis patients. 
Journal of Clinical Microbiology  1996;34(3):520-523.
The clinical course of microsporidiosis caused by Enterocytozoon bieneusi and the pattern of intestinal shedding of spores have not been correlated, at least in part because detection of E. bieneusi in stools is more difficult than detection of other protozoa because of its smaller size and less intense staining. We examined with a modified trichrome stain 124 stool specimens collected over a 2-year follow-up period from 23 human immunodeficiency virus-infected patients with electron microscopic-proven E. bieneusi infection and correlated the results with electron microscopic observations from duodenal biopsy specimens taken at the beginning of the study period. E. bieneusi was detected in the stool at least once in 74% (17 of 23) of all patients, in 100% (9 of 9) of patients in whose tissue moderate or abundant numbers of parasites were seen, and in 57% (8 of 14) of patients in whose tissue few parasites were seen. In two patients with abundant tissue parasites, many microsporidia were detected in every stool specimen (13 of 13) during the follow-up period, whereas among the patients with few tissue parasites, only 23% (15 of 64) of stool specimens were positive. Furthermore, if spore stages as well as plasmodial stages were detected in tissue, stool specimens were more likely to be positive. Although most of the heavily infected stools were from patients with chronic diarrhea, microsporidia were detected in 33, 28, and 42% of stool specimens from patients with nil, intermittent, and chronic diarrhea patterns, respectively. Although quantitation of E. bieneusi spores in stool specimens was closely correlated with quantitation in tissue, it was not correlated with reported patterns of diarrhea.
PMCID: PMC228838  PMID: 8904406
10.  Diarrhoea in adults (acute) 
Clinical Evidence  2008;2008:0901.
Introduction
An estimated 4000 million cases of diarrhoea occurred worldwide in 1996, resulting in 2.5 million deaths.
Methods and outcomes
We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of treatments for acute diarrhoea in adults living in resource-rich countries? What are the effects of treatments for acute mild-to-moderate diarrhoea in adults from resource-rich countries traveling to resource-poor countries? What are the effects of treatments for acute mild-to-moderate diarrhoea in adults living in resource-poor countries? What are the effects of treatments for acute severe diarrhoea in adults living in resource-poor countries? We searched: Medline, Embase, The Cochrane Library and other important databases up to January 2007 (BMJ Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).
Results
We found 71 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.
Conclusions
In this systematic review we present information relating to the effectiveness and safety of the following interventions: antibiotics, antimotility agents, antisecretory agents, bismuth subsalicylate, diet, intravenous rehydration, nasogastric tube rehydration, and oral rehydration solutions (amino acid oral rehydration solution, bicarbonate oral rehydration solution, reduced osmolarity oral rehydration solution, rice-based oral rehydration solution, standard oral rehydration solution).
Key Points
Diarrhoea is watery or liquid stools, usually with an increase in stool weight above 200 g daily and an increase in daily stool frequency. An estimated 4000 million cases of diarrhoea occurred worldwide in 1996, resulting in 2.5 million deaths.
In people from resource-poor countries, antisecretory agents, such as racecadotril, seem to be as effective at improving symptoms of diarrhoea as antimotility agents, such as loperamide, but with fewer adverse effects. Empirical treatment with antibiotics also seems to reduce the duration of diarrhoea and improve symptoms in this population, although it can produce adverse effects such as rash, myalgia, and nausea.Instructing people to refrain from taking any solid food for 24 hours does not appear to be a useful treatment, although the evidence for this is sparse.We don't know how effective oral rehydration solutions or antibiotics plus antimotility agents are in this population, as we did not find any RCTs.
Antisecretory agents, antibiotics, and antimotility agents also appear to be effective in treating people from resource-rich countries who are travelling to resource-poor countries. We don't know whether antibiotics plus antimotility agents are more effective than either treatment alone or placebo. Bismuth subsalicylate is effective in treating travellers' diarrhoea, but less so than loperamide, and with more adverse effects (primarily black tongue and black stools).We don't know the effectiveness of oral rehydration solutions or restricting diet in reducing symptoms of diarrhoea in people travelling to resource-poor countires.
For people from resource-poor countires with mild or moderate diarrhoea, antisecretory agents seem to be as beneficial as antimotility agents, and cause fewer adverse effects (particularly rebound constipation). We didn't find sufficient evidence to allow us to judge the efficacy of antibiotics, antibiotics plus antimotility agents, or oral rehydration solutions in this population.
Oral rehydration solutions are considered to be beneficial in people from resource-poor countries who have severe diarrhoea. Studies have shown that amino acid-based and rice-based oral rehydration solutions are beneficial, but the evidence is less clear about the efficacy of bicarbonate or reduced osmolarity solutions.
We don't know whether intravenous rehydration is more beneficial than oral rehydration or enteral rehydration through a nasogastric tube. We don't know whether antimotility agents, antisecretory agents, antibiotics, or antiobiotics plus antimotility agents are effective for treating people with severe diarrhoea in resource-poor countries.
PMCID: PMC2907942  PMID: 19450323
11.  Rotavirus Antigenemia in Children Is Associated with Viremia 
PLoS Medicine  2007;4(4):e121.
Background
Antigenemia is commonly detected in rotavirus-infected children. Although rotavirus RNA has been detected in serum, definitive proof of rotavirus viremia has not been shown. We aimed to analyze a defined patient population to determine if infectious virus could be detected in sera from children with rotavirus antigenemia.
Methods and Findings
Serum samples obtained upon hospitalization from children with gastroenteritis (57 stool rotavirus-positive and 41 rotavirus-negative), children with diagnosed bronchiolitis of known (n = 58) or unknown (n = 17) viral etiology, children with noninfectious, nonchronic conditions (n = 17), and healthy adults (n = 28) were tested for rotavirus antigen by enzyme immunoassay (EIA). Results of serum antigen testing were assessed for association with clinical and immunological attributes of the children. Rotavirus antigenemia was detected in 90% (51/57) of children with rotavirus-positive stools, in 89% (8/9) of children without diarrhea but with rotavirus-positive stools, in 12% (2/17) of children with bronchiolitis of unknown etiology without gastroenteritis, and in 12% (5/41) of children with gastroenteritis but with rotavirus-negative stools. Antigenemia was not detected in sera from children with noninfectious nonchronic conditions, children with bronchiolitis of known etiology and no gastroenteritis, or healthy adults. Neither age nor timing of serum collection within eight days after onset of gastroenteritis significantly affected levels of antigenemia, and there was no correlation between antigenemia and viral genotype. However, there was a negative correlation between serum rotavirus antigen and acute rotavirus-specific serum IgA (r = −0.44, p = 0.025) and IgG (r = −0.40, p = 0.01) titers. We examined 11 antigen-positive and nine antigen-negative sera for infectious virus after three blind serial passages in HT-29 cells using immunofluorescence staining for rotavirus structural and nonstructural proteins. Infectious virus was detected in 11/11 (100%) sera from serum antigen-positive children and in two out of nine (22%) sera samples from antigen-negative children (p = 0.002).
Conclusions
Most children infected with rotavirus are viremic. The presence of viremia is directly related to the detection of antigenemia and is independent of the presence of diarrhea. Antigenemia load is inversely related to the titer of antirotavirus antibody in the serum. The finding of infectious rotavirus in the blood suggests extraintestinal involvement in rotavirus pathogenesis; however, the impact of rotavirus viremia on clinical manifestations of infection is unknown.
A study of 57 children with rotavirus-positive stools found that most were viremic, and that the presence of viremia was directly related to antigenemia and independent of the presence of diarrhea.
Editors' Summary
Background.
Rotavirus is a type of virus that is the commonest cause of severe diarrhea among children worldwide. It is passed from one person to another when virus present in the stool of an infected person is swallowed by another individual. The infection causes vomiting, watery diarrhea, and fever; many children need to be hospitalized as a result and globally more than 600,000 children are thought to die as a result of rotavirus infections per year. Evidence from single case descriptions of infected children have suggested that rotavirus might also cause symptoms outside of the gut—for example, in the lungs or brain. Previous studies have found fragments of rotavirus, for example RNA or parts of virus protein, in tissues outside of the gut such as liver, kidney, blood, and heart. However, simply finding fragments such as RNA or protein does not necessarily mean that rotavirus infects these tissues.
Why Was This Study Done?
These researchers wanted to find out whether rotavirus was present in the blood of infected children. If evidence of rotavirus in the blood was found, this might help explain why some children infected with rotavirus have symptoms affecting organs other than the gut.
What Did the Researchers Do and Find?
In this study, five groups of patients were recruited and tests were done on each to find out whether infectious rotavirus was present in their bloodstream, and also whether the researchers could detect rotavirus components in blood using antibodies against particular parts of the rotavirus particle. The five groups of patients that were compared included children hospitalized with gastroenteritis; children hospitalized with noninfectious conditions; healthy adult laboratory workers; children with lung infections from known viruses; and finally children with lung infections of unknown cause. The researchers found that among the children with gastroenteritis who had rotavirus in their stool, 90% also had evidence of rotavirus particles in their bloodstream. By contrast, control individuals (either children who were hospitalized with noninfectious conditions or healthy adults) did not have rotavirus particles in blood. A small proportion of children with gastroenteritis but no rotavirus in their stool did have rotavirus particles in blood. Interestingly, a small proportion of the children who had lung infections (but in whom no known virus had been identified as the cause) showed evidence of rotavirus in their bloodstreams. Finally, in a group of 11 children with evidence of rotavirus particles in their bloodstreams, all were found to also have infectious virus present in the blood.
What Do These Findings Mean?
These results show that rotavirus is able to spread beyond the gut and into the bloodstream. The finding that rotavirus can spread into the bloodstream may explain some earlier suggestions that rotavirus is responsible for symptoms outside of the gut. However, it is not yet clear how commonly children with rotavirus have other symptoms resulting from the virus spreading into their bloodstream.
Additional Information.
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.0040121.
Read the related PLoS Medicine Perspective article by David Candy
Information from the World Health Organization Initiative for Vaccine Research on rotavirus disease burden; see also the Rotavirus Vaccine Program, a partnership that aims to develop rotavirus vaccines appropriate for use in developing countries
Information from the US Centers for Disease Control and Prevention about rotavirus
Health Encyclopedia entry from the UK's NHS Direct on Rotavirus
doi:10.1371/journal.pmed.0040121
PMCID: PMC1852122  PMID: 17439294
12.  An In-Depth Analysis of a Piece of Shit: Distribution of Schistosoma mansoni and Hookworm Eggs in Human Stool 
Background
An accurate diagnosis of helminth infection is important to improve patient management. However, there is considerable intra- and inter-specimen variation of helminth egg counts in human feces. Homogenization of stool samples has been suggested to improve diagnostic accuracy, but there are no detailed investigations. Rapid disintegration of hookworm eggs constitutes another problem in epidemiological surveys. We studied the spatial distribution of Schistosoma mansoni and hookworm eggs in stool samples, the effect of homogenization, and determined egg counts over time in stool samples stored under different conditions.
Methodology
Whole-stool samples were collected from 222 individuals in a rural part of south Côte d'Ivoire. Samples were cut into four pieces and helminth egg locations from the front to the back and from the center to the surface were analyzed. Some samples were homogenized and fecal egg counts (FECs) compared before and after homogenization. The effect of stool storing methods on FECs was investigated over time, comparing stool storage on ice, covering stool samples with a water-soaked tissue, or keeping stool samples in the shade.
Principal Findings
We found no clear spatial pattern of S. mansoni and hookworm eggs in fecal samples. Homogenization decreased S. mansoni FECs (p = 0.026), while no effect was observed for hookworm and other soil-transmitted helminths. Hookworm FECs decreased over time. Storing stool samples on ice or covered with a moist tissue slowed down hookworm egg decay (p<0.005).
Conclusions/Significance
Our findings have important implications for helminth diagnosis at the individual patient level and for epidemiological surveys, anthelmintic drug efficacy studies and monitoring of control programs. Specifically, homogenization of fecal samples is recommended for an accurate detection of S. mansoni eggs, while keeping collected stool samples cool and moist delayed the disintegration of hookworm eggs.
Author Summary
An accurate diagnosis of parasitic worm (helminth) infections is important for adequate patient treatment and disease control programs. Helminth eggs in human stool samples are used as an indicator of infection intensity and morbidity. However, little is known about the exact distribution of helminth eggs in stool samples. Homogenization has been suggested to improve the diagnostic accuracy. Hookworm eggs disintegrate over time, which makes their detection challenging in epidemiological surveys. We determined the location of helminth eggs in entire stool samples from 222 individuals in Côte d'Ivoire. We also investigated whether homogenization has an effect on the detection of eggs, and determined egg counts over time in stool samples stored on ice, covered with a moist tissue, or kept in the shade. No clear pattern of helminth egg distribution was found in human stool samples. Homogenization resulted in more accurate egg counts of the blood fluke Schistosoma mansoni, while it did not affect other helminths. Keeping stool samples on ice or covered with a wet tissue slows down the disintegration of hookworm eggs. Our findings have important implications for individual patient management and the design and implementation of epidemiological surveys and helminth disease control programs.
doi:10.1371/journal.pntd.0001969
PMCID: PMC3527364  PMID: 23285307
13.  Diarrhoea in adults (acute) 
Clinical Evidence  2011;2011:0901.
Introduction
An estimated 4.6 billion cases of diarrhoea occurred worldwide in 2004, resulting in 2.2 million deaths.
Methods and outcomes
We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of treatments for acute diarrhoea in adults living in resource-rich countries? What are the effects of treatments for acute mild-to-moderate diarrhoea in adults from resource-rich countries travelling to resource-poor countries? What are the effects of treatments for acute mild-to-moderate diarrhoea in adults living in resource-poor countries? What are the effects of treatments for acute severe diarrhoea in adults living in resource-poor countries? We searched: Medline, Embase, The Cochrane Library, and other important databases up to January 2010 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).
Results
We found 72 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.
Conclusions
In this systematic review we present information relating to the effectiveness and safety of the following interventions: antibiotics, antimotility agents, antisecretory agents, bismuth subsalicylate, diet, intravenous rehydration, nasogastric tube rehydration, oral rehydration solutions (amino acid oral rehydration solution, bicarbonate oral rehydration solution, reduced osmolarity oral rehydration solution, rice-based oral rehydration solution, standard oral rehydration solution), vitamin A supplementation, and zinc supplementation.
Key Points
Diarrhoea is an alteration in normal bowel movement, characterised by increased frequency, volume, and water content of stools, often defined clinically as an increase in stool frequency to three or more liquid or semi-formed motions in 24 hours. An estimated 4.6 billion cases of diarrhoeal illness occurred worldwide in 2004, causing 2.2 million deaths, 1.5 million of which were in children.
This review examines the effects of treatments in adults.
In people from resource-poor countries, antisecretory agents, such as racecadotril, seem to be as effective at improving symptoms of diarrhoea as antimotility agents, such as loperamide, but with fewer adverse effects. Empirical treatment with antibiotics also seems to reduce the duration of diarrhoea and improve symptoms in this population, although it can produce adverse effects such as rash, myalgia, and nausea.Instructing people to refrain from taking any solid food for 24 hours does not seem to be a useful treatment, although the evidence for this is sparse.We don't know how effective oral rehydration solutions or antibiotics plus antimotility agents are in this population, as we did not find any RCTs.
Antisecretory agents, antibiotics, and antimotility agents also seem to be effective in treating people from resource-rich countries who are travelling to resource-poor countries. Antibiotics plus antimotility agents may be more effective than antibiotics alone at reducing the duration of diarrhoea in people with travellers' diarrhoea. Bismuth subsalicylate is effective in treating travellers' diarrhoea, but less so than loperamide, and with more adverse effects (primarily black tongue and black stools).We don't know the effectiveness of oral rehydration solutions or restricting diet in reducing symptoms of diarrhoea in people travelling to resource-poor countries.
For people from resource-poor countries with mild or moderate diarrhoea, antisecretory agents seem to be as beneficial as antimotility agents, and cause fewer adverse effects (particularly rebound constipation). We didn't find sufficient evidence to allow us to judge the efficacy of antibiotics, antibiotics plus antimotility agents, or oral rehydration solutions in this population.
Oral rehydration solutions are considered to be beneficial in people from resource-poor countries who have severe diarrhoea. Studies have shown that amino acid-based and rice-based oral rehydration solutions are beneficial, but the evidence is less clear about the efficacy of bicarbonate or reduced osmolarity solutions.Rice-based oral rehydration solutions seem more beneficial compared with glucose-based oral rehydration solutions in reducing the duration of severe diarrhoea in resource-poor countries.
We don't know whether intravenous rehydration is more beneficial than oral rehydration or enteral rehydration through a nasogastric tube. We don't know whether antimotility agents, antisecretory agents, antibiotics, or antibiotics plus antimotility agents are effective for treating people with severe diarrhoea in resource-poor countries.We found no evidence on the use of zinc or vitamin A supplementation in adults in a resource-poor setting.
PMCID: PMC3217748  PMID: 21718555
14.  Impact of Rapid Urbanization on the Rates of Infection by Vibrio cholerae O1 and Enterotoxigenic Escherichia coli in Dhaka, Bangladesh 
Background
In Bangladesh, increases in cholera epidemics are being documented with a greater incidence and severity. The aim of this prospective study was to identify the prevalence and importance of V. cholerae O1 and enterotoxigenic Escherichia coli (ETEC) as causal agents of severe diarrhea in a high diarrhea prone urban area in Dhaka city.
Methodology
Systematic surveillance was carried out on all diarrheal patients admitted from Mirpur between March 2008 to February 2010 at the ICDDR, B hospital. Stool or rectal swabs were collected from every third diarrheal patient for microbiological evaluation.
Principal Findings
Of diarrheal patients attending the hospital from Mirpur, 41% suffered from severe dehydration with 39% requiring intravenous rehydration therapy. More diarrheal patients were above five years of age (64%) than those below five years of age (36%). About 60% of the patients above five years of age had severe dehydration compared with only 9% of patients under five years of age. The most prevalent pathogen isolated was Vibrio cholerae O1 (23%) followed by ETEC (11%). About 8% of cholera infection was seen in infants with the youngest children being one month of age while in the case of ETEC the rate was 11%. Of the isolated ETEC strains, the enterotoxin type were almost equally distributed; ST accounted for 31% of strains; LT/ST for 38% and LT for 31%.
Conclusion
V. cholerae O1 is the major bacterial pathogen and a cause of severe cholera disease in 23% of patients from Mirpur. This represents a socioeconomic group that best reflects the major areas of high cholera burden in the country. Vaccines that can target such high risk groups in the country and the region will hopefully be able to reduce the disease morbidity and the transmission of pathogens that impact the life and health of people.
Author Summary
Bangladesh is a country where acute dehydrating diarrhea or cholera is common and is seen at least two times every year and additionally in natural disasters. In addition cholera cases have increased in the country, especially in urban settings such as in the capital city, Dhaka, where the number of hospitalized patients with more severe disease has tremendously increased. In the present observation, we have concentrated on determining the occurrence of diarrhoea caused by the two most common bacterial agents V. cholerae O1 and enterotoxigenic Escherichia coli (ETEC) in a densely populated, disease prone area Mirpur in Dhaka for two years from March 2008 to February 2010. Stool or rectal specimens from diarrheal patients coming to the ICDDR,B hospital from Mirpur were tested for the two bacterial pathogens. We found that V. cholerae O1 was the major bacterial pathogen and a cause of severe cholera disease in 23% of patients (2,647 of a total of 11,395 patients) from Mirpur. We surmise that cholera vaccines, as well as other public health tools that can target such high risk groups in the country, will be able to reduce the disease morbidity and the transmission of pathogens to improve the quality of life in urban settings.
doi:10.1371/journal.pntd.0000999
PMCID: PMC3071362  PMID: 21483709
15.  Value of microscopy in the diagnosis of dysentery associated with invasive Entamoeba histolytica. 
Journal of Clinical Pathology  1994;47(3):236-239.
AIMS--To assess the reliability of the detection of erythrophagocytic amoebic trophozoites in stool samples in the diagnosis of dysentery associated with invasive Entamoeba histolytica. METHODS--Amoebic culture was carried out on single stool samples collected from patients from Mexico, Colombia, and Bangladesh. The stools had been examined by light microscopy. Amoebic dysentery was diagnosed when erythrophagocytic E histolytica trophozoites were observed in a case of bloody diarrhoea. E histolytica isolates were characterised by isoenzyme electrophoresis and results correlated with microscopical findings in stools. Statistical analysis was performed using the chi 2 test. RESULTS--Where erythrophagocytic amoebae had been observed in dysenteric stool specimens the E histolytica phenotype was invariably invasive (p < 0.0001). Observation of erythrophagocytic amoebae in dysentery is 100% specific and predictive of infection with invasive E histolytica. When amoebic culture-positive cases only are considered it is 96% sensitive. In this study E histolytica of zymodeme XIV was more commonly associated with amoebic dysentery than zymodeme II. There was no significant difference between the carriage rate of invasive and non-invasive E histolytica in non-dysenteric diarrhoea. Asymptomatic subjects carried non-invasive E histolytica more frequently than invasive E histolytica. Patients with non-amoebic dysentery, when shown to be infected with E histolytica, carried non-invasive strains (12%). CONCLUSIONS--Sensitivity and specificity of microscopical examination of a single stool specimen for diagnosing amoebic dysentery is very high; intestinal carriage of invasive E histolytica detected by culture is not necessarily an indication of active disease as patients with diarrhoea and asymptomatic subjects shed invasive and non-invasive E histolytica. There are possibly two subpopulations of invasive E histolytica with different pathogenic potential which can be differentiated by zymodeme analysis.
PMCID: PMC501902  PMID: 8163695
16.  Methods for determining disease burden and calibrating national surveillance data in the United Kingdom: the second study of infectious intestinal disease in the community (IID2 study) 
Background
Infectious intestinal disease (IID), usually presenting as diarrhoea and vomiting, is frequently preventable. Though often mild and self-limiting, its commonness makes IID an important public health problem. In the mid 1990s around 1 in 5 people in England suffered from IID a year, costing around £0.75 billion. No routine information source describes the UK's current community burden of IID. We present here the methods for a study to determine rates and aetiology of IID in the community, presenting to primary care and recorded in national surveillance statistics. We will also outline methods to determine whether or not incidence has declined since the mid-1990s.
Methods/design
The Second Study of Infectious Intestinal Disease in the Community (IID2 Study) comprises several separate but related studies. We use two methods to describe IID burden in the community - a retrospective telephone survey of self-reported illness and a prospective, all-age, population-based cohort study with weekly follow-up over a calendar year. Results from the two methods will be compared. To determine IID burden presenting to primary care we perform a prospective study of people presenting to their General Practitioner with symptoms of IID, in which we intervene in clinical and laboratory practice, and an audit of routine clinical and laboratory practice in primary care. We determine aetiology of IID using molecular methods for a wide range of gastrointestinal pathogens, in addition to conventional diagnostic microbiological techniques, and characterise isolates further through reference typing. Finally, we combine all our results to calibrate national surveillance data.
Discussion
Researchers disagree about the best method(s) to ascertain disease burden. Our study will allow an evaluation of methods to determine the community burden of IID by comparing the different approaches to estimate IID incidence in its linked components.
doi:10.1186/1471-2288-10-39
PMCID: PMC2886083  PMID: 20444246
17.  Utility of Multiple-Stool-Specimen Ova and Parasite Examinations in a High-Prevalence Setting 
Journal of Clinical Microbiology  1999;37(8):2408-2411.
A retrospective analysis of the results of 2,704 ova and parasite (O & P) examinations performed on stool specimens collected from 1,374 patients between October 1996 and September 1997 was performed to evaluate the utility of performing O & P examinations on multiple, independently collected stool specimens in a high-prevalence setting. A total of 995 specimens (36.8%) examined during the study contained parasites; 546 (20.2%) contained pathogenic organisms. The positivity rate (54.5%) for the patients from whom three specimens were examined was significantly higher than for the patients from whom either two specimens (33.3%) or a single specimen (19.8%) was submitted for examination. For the group of patients from whom at least 3 specimens were submitted for O & P examination, 373 independent opportunities for diagnosing infection with intestinal parasites could be analyzed. The first stool specimen collected proved to be adequate in only 75.9% (283 of 373) of evaluated cases; however, examination of two specimens increased the sensitivity of O & P detection to 92% (343 of 373). The third specimen collected provided additional information on only 30 of 373 occasions (8%). These data indicate that in populations with a high prevalence of intestinal parasitic infections, two independently collected stool specimens should be subjected to O & P examination to ensure adequate diagnostic sensitivity.
PMCID: PMC85240  PMID: 10405376
18.  Patterns of detection of Strongyloides stercoralis in stool specimens: implications for diagnosis and clinical trials. 
Journal of Clinical Microbiology  1996;34(10):2569-2571.
Reported efficacies of drugs used to treat Strongyloides stercoralis infection vary widely. Because diagnostic methods are insensitive, therapeutic trials generally require multiple negative posttreatment stool specimens as evidence of drug efficacy. However, only a single positive stool specimen is usually required for study enrollment. To determine the reproducibility of detection of S. stercoralis larvae in the stool, 108 asymptomatic infected men submitted 25 g of fresh stool once a week for eight consecutive weeks for examination by the Baermann technique. During the 8-week study, 239 (27.7%) of 864 stool specimens were positive for S. stercoralis. Rates of detection of larvae in the stool specimens ranged from eight of eight specimens in 3 (2.8%) men to none of eight specimens in 36 (33.3%) men. Of 43 men for whom S. stercoralis was detected in at least two of the first four stool specimens, only 1 (2.3%) man tested negative on all of the next four specimens. In comparison, of 29 men who had detectable larvae in only one of the first four specimens, 22 (75.9%) tested negative on all of the next four samples. Thus, if these 29 men had been enrolled in a therapeutic trial between the first and second sets of four specimens, the efficacy of a drug with no activity against this parasite would have been estimated to be 76%. These data suggest that patterns of S. stercoralis detection vary widely among infected persons and that intermittent larval shedding can lead to inflated estimates of drug efficacy. Before a patient is entered in a clinical trial of drug efficacy, four consecutive stool specimens should be examined for S. stercoralis; only persons with two or more positive specimens should be enrolled.
PMCID: PMC229319  PMID: 8880521
19.  Diagnosing norovirus-associated infectious intestinal disease using viral load 
Background
Reverse transcription-polymerase chain reaction (RT-PCR) is the main method for laboratory diagnosis of norovirus-associated infectious intestinal disease (IID). However, up to 16% of healthy individuals in the community, with no recent history of IID, may be RT-PCR positive; so it is unclear whether norovirus is actually the cause of illness in an IID case when they are RT-PCR positive. It is important to identify the pathogen causing illness in sporadic IID cases, for clinical management and for community based incidence studies. The aim of this study was to investigate how faecal viral load can be used to determine when norovirus is the most likely cause of illness in an IID case.
Methods
Real-time RT-PCR was used to determine the viral load in faecal specimens collected from 589 IID cases and 159 healthy controls, who were infected with genogroup II noroviruses. Cycle threshold (Ct) values from the real-time RT-PCR were used as a proxy measure of viral load. Receiver-operating characteristic (ROC) analysis was used to identify a cut-off in viral load for attributing illness to norovirus in IID cases.
Results
One hundred and sixty-nine IID cases and 159 controls met the inclusion criteria for the ROC analysis. The optimal Ct value cut-off for attributing IID to norovirus was 31. The same cut-off was selected when using healthy controls, or IID cases who were positive by culture for bacterial pathogens, as the reference negative group. This alternative reference negative group can be identified amongst specimens routinely received in clinical virology laboratories.
Conclusion
We demonstrated that ROC analysis can be used to select a cut-off for a norovirus real time RT-PCR assay, to aid clinical interpretation and diagnose when norovirus is the cause of IID. Specimens routinely received for diagnosis in clinical virology laboratories can be used to select an appropriate cut-off. Individual laboratories can use this method to define in-house cut-offs for their assays, to provide the best possible diagnostic service to clinicians and public health workers. Other clinical and epidemiological information should also be considered for patients with Ct values close to the cut-off, for the most accurate diagnosis of IID aetiology.
doi:10.1186/1471-2334-9-63
PMCID: PMC2698835  PMID: 19442278
20.  A large point-source outbreak of Salmonella Typhimurium linked to chicken, pork and salad rolls from a Vietnamese bakery in Sydney 
Introduction
In January 2011, Sydney South West Public Health Unit was notified of a large number of people presenting with gastroenteritis over two days at a local hospital emergency department (ED).
Methods
Case-finding was conducted through hospital EDs and general practitioners, which resulted in the notification of 154 possible cases, from which 83 outbreak cases were identified. Fifty-eight cases were interviewed about demographics, symptom profile and food histories. Stool samples were collected and submitted for analysis. An inspection was conducted at a Vietnamese bakery and food samples were collected and submitted for analysis. Further case ascertainment occurred to ensure control measures were successful.
Results
Of the 58 interviewed cases, the symptom profile included diarrhoea (100%), fever (79.3%) and vomiting (89.7%). Salmonella Typhimurium multiple-locus-variable number tandem repeats analysis (MLVA) type 3–10–8-9–523 was identified in 95.9% (47/49) of stool samples. Cases reported consuming chicken, pork or salad rolls from a single Vietnamese bakery. Environmental swabs detected widespread contamination with Salmonella at the premises.
Discussion
This was a large point-source outbreak associated with the consumption of Vietnamese-style pork, chicken and salad rolls. These foods have been responsible for significant outbreaks in the past. The typical ingredients of raw egg butter or mayonnaise and pate are often implicated, as are the food-handling practices in food outlets. This indicates the need for education in better food-handling practices, including the benefits of using safer products. Ongoing surveillance will monitor the success of new food regulations introduced in New South Wales during 2011 for improving food-handling practices and reducing foodborne illness.
doi:10.5365/WPSAR.2012.3.1.001
PMCID: PMC3729077  PMID: 23908908
21.  Use of a Cholera Rapid Diagnostic Test during a Mass Vaccination Campaign in Response to an Epidemic in Guinea, 2012 
Background
During the 2012 cholera outbreak in the Republic of Guinea, the Ministry of Health, supported by Médecins Sans Frontières - Operational Center Geneva, used the oral cholera vaccine Shanchol as a part of the emergency response. The rapid diagnostic test (RDT) Crystal VC, widely used during outbreaks, detects lipopolysaccharide antigens of Vibrio cholerae O1 and O139, both included in Shanchol. In the context of reactive use of a whole-cell cholera vaccine in a region where cholera cases have been reported, it is essential to know what proportion of vaccinated individuals would be reactive to the RDT and for how long after vaccination.
Methodology/Principal Findings
A total of 108 vaccinated individuals, selected systematically among all persons older than one year, were included at vaccination sites and 106 were included in the analysis. Stools samples of this cohort of vaccinated participants were collected and tested with the RDT every day until the test was negative for two consecutive visits or for a maximum of 7 days. A total of 94.3% of cholera vaccine recipients had a positive test after vaccination; all except one of these positive results were reactive only with the O139 antigen. The mean time to become negative in those with an initial positive result after vaccination was 3.8 days, standard deviation 1.1 days.
Conclusions/Significance
The RDT Crystal VC becomes positive in persons recently vaccinated against cholera, although almost exclusively to the O139 antigen. This reactivity largely disappeared within five days after vaccination. These results suggest that the test can be used normally as soon as 24 hours after vaccination in a context of O1 epidemics, which represent the vast majority of cases, and after a period of five days in areas where V. cholerae O139 is present. The reason why only O139 test line became positive remains to be investigated.
Author Summary
The rapid diagnostic test (RDT) Crystal VC detects lipopolysaccharide antigens from V. cholerae O1 and O139 in stool samples, which are also present in the oral cholera vaccine Shanchol. It is important to take into consideration the possibility of a positive result to the RDT due to vaccination and not to cholera in recently vaccinated individuals. During a large mass cholera vaccination campaign in Kabak (Guinea) in 2012, we conducted a study to estimate the proportion of positive results to the RDT in recipients of the oral cholera vaccine at different time points after vaccination. The results of this study show that ingestion of the cholera vaccine led to a positive RDT, although almost exclusively to the O139 antigen, in the majority of vaccinated people. From the fifth day after vaccination, only a small minority of vaccinated individuals remained positive for the RDT and none of the specimens tested the seventh day of follow-up were positive. Our findings provide the first data on the use of the RDT Crystal VC in vaccinated people. This test should be used carefully during the first week after reactive mass oral cholera vaccination campaigns in areas where V. cholerae O139 is present.
doi:10.1371/journal.pntd.0002366
PMCID: PMC3744445  PMID: 23967359
22.  Intestinal carriage of Bacillus cereus: faecal isolation studies in three population groups. 
The Journal of Hygiene  1985;95(3):629-638.
The results of examinations of stools for Bacillus cereus among three unrelated groups of individuals are presented. The groups consisted of (1) healthy school-children aged 6-11 years in a rural region of South Africa examined during each of the four seasons of the year; (2) 15 healthy volunteers comprising staff of a London microbiology laboratory and their families examined on each of 3 consecutive weeks; (3) 75 unrelated young children, 2 months to 5 years of age, in a second rural region of South Africa examined during a pilot study of 1 week's duration on the aetiology of rural gastroenteritis. The stools of the last group were submitted as being related to present or recent diarrhoea in the respective children. In group 1, B. cereus isolation rates ranged from 24.3% at the autumn visit to 43% at the summer visit with a significantly higher rate of isolation in the summer than at other seasons of the year (P less than 0.05). B. cereus was isolated from 40% of group 2 volunteers on week 1, none on week 2 and 20% on week 3. The organism was detected in the 12 positive specimens at levels of approximately 10(2)/g and constituted 2.5-30% of the total aerobic spore-forming bacillus population in the stools. In group 3, B. cereus was recovered from 18.7% of the stool samples and was isolated consecutively with other pathogens (enteropathogenic Escherichia coli and rotavirus) on only five occasions. In groups 1 and 3, less than 5% of the stools had '3+' levels of B. cereus (greater than 10 colonies per direct plate culture). B. cereus was readily isolated from all of 10 food samples, representative of the typical diet of the group 1 individuals, and was present in substantial numbers (10(4) to 5.5 X 10(6)/g) in half of them. The isolation results, supported by serotyping, indicated that carriage of B. cereus in stools is transient and its presence at any one time reflects solely its intake with foods.
PMCID: PMC2129566  PMID: 3937856
23.  Loperamide Therapy for Acute Diarrhea in Children: Systematic Review and Meta-Analysis 
PLoS Medicine  2007;4(3):e98.
Background
Loperamide is widely used in adults for acute diarrhea. However, its use in children has been discouraged by the World Health Organization and the American Academy of Pediatrics owing to concerns over safety and efficacy in young children.
Methods and Findings
To assess the efficacy and adverse effects of loperamide compared with placebo for acute diarrhea in children, we reviewed Medline, EMBase, the Cochrane Central Register of Controlled Trials, and bibliographies of known clinical trials and of review articles, and we also interviewed key investigators in the field. We undertook a systematic review and meta-analysis of randomized controlled trials of children younger than 12 y of age with acute diarrhea, comparing loperamide with placebo. Included trials reported data on diarrhea duration or severity, or provided data on adverse effects. Compared with patients who received placebo, patients allocated to loperamide were less likely to continue to have diarrhea at 24 h (prevalence ratio 0.66, 95% confidence interval [CI]: 0.57 to 0.78), had a shorter duration of diarrhea by 0.8 d (95% CI: 0.7 to 0.9 d), and had a lower count of stools at 24 h (0.84, 95% CI: 0.77 to 0.92). Results were similar when random-effects summaries were estimated. Serious adverse events, defined as ileus, lethargy, or death, were reported in eight out of 927 children allocated to loperamide (0.9%, 95% CI: 0.4% to 1.7%). Serious adverse events were not reported in any of the 764 children allocated to placebo (0%, 95% CI: 0% to 0.5%). Among the children allocated to loperamide, serious adverse events were reported only among children younger than 3 y.
Conclusions
In children who are younger than 3 y, malnourished, moderately or severely dehydrated, systemically ill, or have bloody diarrhea, adverse events outweigh benefits even at doses ≤0.25 mg/kg/d. In children who are older than 3 y with no/minimal dehydration, loperamide may be a useful adjunct to oral rehydration and early refeeding.
In seriously ill children under 3 years of age with diarrhea the adverse effects of loperamide outweighed the benefits, but the drug could be useful as part of treatment for other children.
Editors' Summary
Background.
While diarrhea is often thought of as a mild, inconvenient condition, it is estimated that, worldwide, 1.6–2.5 million children under 5 y old die each year from diarrhea, most of them in developing countries. Dehydration is the key factor in the deaths of these children. In richer countries, diarrhea is rarely deadly, but it has been calculated that, in the United States, the annual national health-care cost associated with the condition amounts to around US$1.5 billion. Some of the cost results from the purchase of anti-diarrheal drugs. Loperamide is one of the most widely used of these drugs. In most countries, it can be obtained without a prescription. The use of loperamide is intended to reduce the frequency of bowel movements, but taking it will not lead to rehydration, nor will it kill the infectious organisms responsible for the condition.
Why Was This Study Done?
The World Health Organization and other health authorities have concerns that loperamide may not be effective in young children and that it may not be safe. In the United States, the Food and Drug Administration approves its use for children older than 2 y of age. The researchers wanted to know whether loperamide could play a useful part in treating diarrhea in children.
What Did the Researchers Do and Find?
They did not do any new work with children suffering from diarrhea. Instead, they searched the medical literature for previously conducted trials involving the use of loperamide. They used these previously conducted trials to estimate whether use of loperamide influenced the duration of diarrhea or the number of diarrheal stools in children under 12 y of age. They also used these trials to examine adverse effects of loperamide. In total they found 13 studies that met the criteria they had set for inclusion in their study. More than 900 children in these studies had been given loperamide for their diarrhea; each trial also had a control group of children whose treatment did not include loperamide. Most of the children in the studies had only mild diarrhea. The researchers found that, compared with children in the control groups, those treated with loperamide were less likely to continue to have diarrhea 24 h later, had a shorter duration of diarrhea, and had a lower count of diarrheal stools. However, eight of the children given loperamide and none of the control group did have serious adverse effects. All those who had serious adverse effects were less than 3 y of age.
What Do These Findings Mean?
The researchers concluded that if a child is less than 3 y of age, malnourished, moderately or severely dehydrated, or has bloody diarrhea, the risk of adverse events from loperamide treatment outweighs the benefits, even at low doses. In other children, loperamide may be a useful part of treatment. However, they advise that rehydrating the child (by giving fluids orally) and progressively returning him or her to a normal diet should still be the main focus in the treatment of childhood diarrhea.
Additional Information.
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.0040098.
For advice on the treatment of diarrhea, visit the Web sites of BestTreatments (produced by BMJ Publications) and of FamilyDoctor (produced by the American Academy of Family Physicians)
The World Health Organization has a Web page about diarrhea that gives a global perspective on this major cause of childhood death
UNICEF (the children's organization of the United Nations) includes diarrhea in its Facts for Life series, which aims to provide parents and other caregivers with the information they need to save and improve children's lives; the messages contained in Facts for Life are based on the latest scientific findings, but are presented in nontechnical language
doi:10.1371/journal.pmed.0040098
PMCID: PMC1831735  PMID: 17388664
24.  Prevalence of gastrointestinal infection among international travellers returning to Canada 
Objective:
To describe the prevalence of parasitic and bacterial gastrointestinal infection (excluding enterotoxigenic Escherichia coli) among international travellers attending the International Travel Clinic at The University of Calgary.
Methods:
Data were abstracted from the records of the first visit after travel of all persons making a post travel visit between January 1, 1986 and March 31, 1990.
Results:
Data were available for 886 first visits (840 persons). Stools were submitted by 692 travellers. The frequency of stool submission varied by the duration of travel abroad, and the frequency of diarrhea either during or after the trip was greater among those who had submitted a stool specimen. The prevalence of stools positive for ova, parasites or pathogenic bacteria was 41.2%. When only pathogenic organisms were considered, the prevalence of infection was 19.4%. The most commonly isolated pathogenic parasites were Dientamoeba fragilis, Giardia lamblia, and Entamoeba histolytica. The most commonly isolated bacteria were Campylobacter species and Salmonella species.
Conclusions:
Although the prevalence of positive stool screens among returned travellers in this population was high, only about one-fifth of persons tested were positive for pathogens.
PMCID: PMC3250779  PMID: 22346439
Diarrhea; Diarrhea prevention and control; Epidemiology; Retrospective studies; Travel
25.  Improved stool concentration procedure for detection of Cryptosporidium oocysts in fecal specimens. 
Journal of Clinical Microbiology  1992;30(11):2869-2873.
Epidemiologic and laboratory data suggest that coprodiagnostic methods may fail to detect Cryptosporidium oocysts in stool specimens of infected patients. To improve the efficacy of stool concentration procedures, we modified different steps of the Formalin-ethyl acetate (FEA) stool concentration technique and evaluated these modifications by examining stool samples seeded with known numbers of Cryptosporidium oocysts. Because these modifications failed to improve oocyst detection, we developed a new stool concentration technique that includes FEA sedimentation followed by layering and flotation over hypertonic sodium chloride solution to separate parasites from stool debris. Compared with the standard FEA procedure, this technique improved Cryptosporidium oocyst detection. The sensitivities of the two concentration techniques were similar for diarrheal (watery) stool specimens (100% of watery stool specimens seeded with 5,000 oocysts per g of stool were identified as positive by the new technique, compared with 90% of stools processed by the standard FEA technique). However, the most significant improvement in diagnosis occurred with formed stool specimens that were not fatty; 70 to 90% of formed stool specimens seeded with 5,000 oocysts were identified as positive by the new technique, compared with 0% of specimens processed by the standard FEA technique. One hundred percent of formed specimens seeded with 10,000 oocysts were correctly diagnosed by using the new technique, while 0 to 60% of specimens processed by the standard FEA technique were found positive. Similarly, only 50 to 90% of stool specimens seeded with 50,000 oocysts were identified as positive by using the standard FEA technique, compared with a 100% positive rate by the new technique. The new stool concentration procedure provides enhanced detection of Cryptosporidium oocysts in all stool samples.
PMCID: PMC270544  PMID: 1452656

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