Before the introduction of the conjugate vaccine, Haemophilus influenzae serotype b (Hib) was the leading cause of bacterial meningitis in children. Although successful in reducing Hib cases, the vaccine confers no protection against other serotypes of H influenzae, such as a (Hia), or f (Hif). The emergence of invasive disease caused by non-Hib in northwestern Ontario (38 cases between 2002 and 2008) with predominance of Hia was previously reported by the authors. At that time, no cases of pediatric meningitis caused by H influenzae were recorded in the region. Continued surveillance identified 12 new cases of invasive non-Hib between January 2009 and July 2011. Among these cases, three young children developed meningitis with severe complications caused by Hia or Hif. The present article describes these cases along with the characteristics of recent H influenzae isolates from the region, (ie, their genetic background and antibiotic sensitivity). The findings point to the clonal nature of circulating Hia strains as well as to an increase in frequency and severity of pediatric invasive H influenzae infections in northwestern Ontario.
Case series; Haemophilus influenzae; Meningitis; Serotype a; Serotype f
Bacterial pathogens belonging to the genus Acinetobacter cause serious infections in immunocompromised individuals that are very difficult to treat due to their extremely high resistance to many antibiotics.
To investigate the role of resistance-nodulation-division (RND) pumps and porins in the antibiotic resistance of Acinetobacter species collected from Canadian hospitals.
Clinical isolates of Acinetobacter species collected from Canadian hospitals were analyzed for the expression of genes encoding RND pumps (adeB, adeG, adeJ, AciBau_2746 and AciBau_2436) and outer membrane porins (carO, 33 kDa porin and oprD) using quantitative reverse transcription (qRT) polymerase chain reaction. Species identification of the isolates was performed using a multiplex polymerase chain reaction method for gyrB.
The expression of RND pump-encoding genes was widespread in the clinical isolates of Acinetobacter species, with each of the isolates expressing at least one RND pump. adeG was found to be overexpressed in all of the isolates, while adeB was found to be overexpressed in only two isolates. Among the porin-encoding genes, the expression of carO was considerably downregulated among the majority of isolates.
The present study was the first to analyze the expression of RND pump- and porin-encoding genes in the clinical isolates of Acinetobacter species from Canadian hospitals. The overexpression of genes encoding RND pumps and the downregulation of genes encoding porins was common in clinical isolates of Acinetobacter species from Canadian hospitals, with the AdeFGH pump being the most commonly expressed RND pump.
Acinetobacter; Antibiotic resistance; Gene expression
Approximately one in 10 hospitalized patients will acquire a nosocomial infection (NI) after admission to hospital, of which 71% are due to respiratory viruses, including the respiratory syncytial virus (RSV). NIs are concerning and lead to prolonged hospitalizations. The economics of NIs are typically described in generalized terms and specific cost data are lacking.
To develop an evidence-based model for predicting the risk and cost of nosocomial RSV infection in pediatric settings.
A model was developed, from a Canadian perspective, to capture all costs related to an RSV infection hospitalization, including the risk and cost of an NI, diagnostic testing and infection control. All data inputs were derived from published literature. Deterministic sensitivity analyses were performed to evaluate the uncertainty associated with the estimates and to explore the impact of changes to key variables. A probabilistic sensitivity analysis was performed to estimate a confidence interval for the overall cost estimate.
The estimated cost of nosocomial RSV infection adds approximately 30.5% to the hospitalization costs for the treatment of community-acquired severe RSV infection. The net benefits of the prevention activities were estimated to be equivalent to 9% of the total RSV-related costs. Changes in the estimated hospital infection transmission rates did not have a significant impact on the base-case estimate.
The risk and cost of nosocomial RSV infection contributes to the overall burden of RSV. The present model, which was developed to estimate this burden, can be adapted to other countries with different disease epidemiology, costs and hospital infection transmission rates.
Nosocomial infection; Pediatrics; Respiratory syncytial virus
Approximately 26% of Canadians living with HIV are unaware of their status. Point-of-care (POC) HIV tests have been introduced to simplify and expand HIV testing.
To evaluate the feasibility and acceptability of POC testing in an emergency department (ED) setting in Winnipeg, Manitoba.
A cross-sectional study of unselected adults presenting to the ED at the Health Sciences Centre Hospital (Winnipeg, Manitoba) was performed. Study procedures included pre- and post-test counselling, administration of the INSTI HIV-1/HIV-2 Antibody Test (bioLytical Laboratories, Canada) and a brief questionnaire. Venous blood samples were collected from participants for confirmatory testing on all reactive and indeterminate specimens.
In total, 501 adults participated in the study. The majority of participants were younger than 40 years of age, approximately one-half (48.5%) were women and 53% self-identified as Aboriginal. Nearly one-half (49.1%) of the participants had undergone previous HIV testing, although 63% of these tests were performed more than a year earlier. A total of seven individuals tested reactive with the POC test, all of whom were confirmed positive using serological testing (1.4%) and were linked to an HIV specialist within 24 h. Nearly all of the participants (96%) reported satisfaction with the test and believed it belonged in the ED (93%).
Of the participants tested, 1.4% tested reactive for HIV, which is significantly higher than the reported prevalence in Manitoba and in other similar studies conducted in North America. Furthermore, all individuals were linked to timely care. The present study demonstrated that this particular busy tertiary care ED is an important and feasible location for HIV POC testing.
Emergency departments; HIV; Testing
Chagas disease is caused by the protozoan parasite Trypanosoma cruzi and is endemic in many countries in Latin America, where infected bugs of the Triatominea subfamily carry the parasite in the gut and transmit it to humans through fecal contamination of a bite. However, vertical transmission and transmission through blood transfusion and organ transplantation is well documented. Increasing immigration from endemic countries to North America has prompted blood operators, including Canadian Blood Services and Hema Quebec, to initiate blood donor testing for Chagas antibody. In the present report, an unusual case of vertical transmission from a mother, most likely infected through blood transfusion, and detected as part of a concurrent seroprevalence study in blood donors is described.
Chagas disease; Transfusion transmission; Vertical transmission
A case of travel-related, subacute, progressive disseminated histoplasmosis in a nonimmunocompromised individual is described. The present case highlights the environmental exposure to Histoplasma capsulatum in Costa Rica, the diagnostic approach and treatment options, as well as new alternatives for salvage therapy for histoplasmosis infection.
Costa Rica; Fever; Histoplasmosis; Posaconazole; Travel
A publicly funded, group A rotavirus (RVA) vaccination program was implemented in Quebec in November 2011.
To evaluate trends in RVA infections and describe circulating genotypes before the implementation of a publicly funded vaccination program.
The Montreal Children’s Hospital (Montreal, Quebec) virology laboratory database was reviewed for RVA ELISA performed between July 2006 and June 2011. A five-week moving average was used to follow the proportion of positive RVA ELISA test results. A season was defined as starting with the first two and ending with the final two consecutive weeks in which the percentage of specimens testing positive for RVA was ≥10%. Duplicate tests were excluded. A random sample of 39 RVA-positive fecal samples from the final season (2010/2011) was genetically characterized: VP4, VP6, VP7 and NSP4 gene segments were genotyped using sequence analysis.
Of the 3403 nonduplicate tests, 433 were RVA positive: 15.1% (2006/2007) to 9.3% (2010/2011) of the samples were positive during the study period, with a proportionally larger decrease in the percentage of positive tests compared with the decrease in the number of tests performed. The most common RVA strain types detected were G9PI1 (n=19) and G1PI1 (n=14), followed by G2PI2 (n=4), G3PI1 (n=1) and G4PI2 (n=1). Mixed RVA infection was observed in two samples.
Before the implementation of the vaccination program, the proportion of positive RVA tests had already begun to steadily decline. The present study was the first to report the genetic makeup of human RVA collected from a Canadian hospital based on the genotyping of four gene segments. The present study provided a baseline with which to monitor the impact of the universal vaccination program.
Epidemiology; Genotyping; Rotavirus; Sequencing
Immunocompromised individuals are more susceptible to complications produced by influenza infection. As a result, solid-organ transplant (SOT) recipients were targeted as a priority group to receive AS03-adjuvanted H1N1 influenza vaccine during 2009.
To evaluate seroconversion after one dose of adjuvanted pandemic influenza H1N1 (pH1N1) vaccine in SOT recipients.
Adult SOT recipients were enrolled to receive one 3.75 μg dose of adjuvanted pH1N1 vaccine. Serological status was tested using a hemagglutination inhibition assay before and two and four weeks postvaccination.
The five SOT recipients (one liver, two kidney and two lung transplants) had a median age of 50 years (range 36 to 53 years), and three were male, who were a median time of three years (range two months to 15 years) post-transplant. All patients were on a double or triple immunosuppressive regimen. The prevaccination pH1N1 titre was 1:10 in four patients and 1:40 in one patient. Seroprotection was observed only in one patient, with a rise in titre from 1:40 at baseline to 1:320 at both two and four weeks after vaccination. This lung transplant recipient had documented previous infection with pH1N1.
Results of the present small study call into question whether one dose of adjuvanted pH1N1 vaccine can provide seroprotection in SOT recipients.
H1N1; Immunogenicity; Influenza; Solid organ; Transplant; Vaccine
Pediatric data regarding cytomegalovirus (CMV) infections in pediatric patients receiving umbilical cord blood (UCB) transplantation are sparse.
To determine whether UCB transplantation increases the risk of CMV infection and disease compared with other graft sources.
The medical files of patients who underwent allogeneic hematopoietic stem cell transplantation at CHU Ste-Justine (Montreal, Quebec) from April 2000 to December 2006 were retrospectively reviewed. A Cox proportional hazard model was used to assess the effect of potential predictors of outcomes.
A total of 176 patients with a median age of nine years (range 0.1 to 18 years) underwent hematopoietic stem cell transplantation. The source of stem cells were UCB, bone marrow and peripheral blood stem cells in 86, 86 and four of the cases, respectively. CMV infection occurred in 29 patients (16%). At day 100 post-transplantation, the rate of CMV infection was 13% in UCB transplant recipients (11 of 86) versus 20% in those with other sources of graft (18 of 90) (P=0.19). Positive CMV serology of the recipient and leukocyte depletion were two independent variables associated with an increased risk of CMV infection. Among infected patients, six developed CMV disease (20.7%). The rate of CMV disease one year after infection was 49% in patients who received UCB (five of 11) and 6% in others (one of 18). This difference was significant by univariate (P=0.01) but not by multivariate analysis.
In the setting of the current study, with a moderate CMV infection rate (16.5%), UCB transplantation did not appear to increase the risk of CMV infection and disease.
Children; Cytomegalovirus; Hematopoietic stem cell transplant; Umbilical cord blood
A population-based study was conducted over a two-year period in the Perth District (PD) and Wellington-Dufferin-Guelph (WDG) health units in Ontario to document antimicrobial resistance and antimicrobial use associated with clinical cases of laboratory-confirmed campylobacteriosis.
Etest (bioMérieux SA, France) was used to determine the minimum inhibitory concentration of amoxicillin/clavulanic acid, ampicillin, chloramphenicol, ciprofloxacin (CIP), clindamycin, erythromycin (ERY), gentamicin, nalidixic acid and tetracycline. Data regarding antimicrobial use were collected from 250 cases.
Of the 250 cases, 165 (65.7%) reported staying home or being hospitalized due to campylobacteriosis. Fifty-four per cent of cases (135 of 249) reported taking antimicrobials to treat campylobacteriosis. In 115 cases (51.1%), fecal culture results were not used for treatment decisions because they were not available before the initiation of antimicrobial treatment and/or they were not available before the cessation of symptoms. Of the 250 cases, 124 (49.6%) had available Campylobacter isolates, of which 66 (53.2%) were resistant to at least one of the antimicrobials tested. No resistance to ampicillin, chloramphenicol or gentamicin was found in these isolates. Six isolates (4.8%) were resistant to CIP. Two isolates (1.6%) were resistant to ERY; however, no isolates were resistant to both CIP and ERY.
Prudent use practices should be promoted among physicians to reduce the use of antimicrobials for the treatment of gastroenteritis in general and campylobacteriosis in particular, as well as to minimize the future development of resistance to these antimicrobials in Campylobacter species.
Antimicrobial resistance; Antimicrobial use; Campylobacter; Canada; Ontario
The clinical presentation and diagnosis of malaria involving a family with seven children who arrived in Canada as refugees is reported. Discrepancies in front-line testing using microscopy and rapid diagnostic tests compared with confirmatory testing using real-time polymerase chain reaction in this cluster of symptomatic and asymptomatic patients were identified.
Diagnosis; Malaria; Refugees
Mycotic aneurysms, defined as irreversible dilation of an artery due to destruction of the vessel wall by infection, are rare but are associated with a high risk of rupture if not treated promptly. The case of a healthy 52-year-old smoker who presented with pyrexia, rigors, night sweats and severe right leg pain with swelling is presented. He was diagnosed with a superficial femoral artery mycotic aneurysm, with Salmonella enteritidis as the causative agent. He was treated with high-dose antibiotics, local debridement and autologous reconstruction. A high index of suspicion is needed to make the correct diagnosis in these cases. Prompt surgical intervention and antimicrobial therapy are the cornerstones of treatment to reduce the associated high morbidity and mortality.
Aneurysm bacteriology; Femoral; Mycotic; Pseudoaneurysm; Salmonella; SFA
Anicteric leptospirosis is a self-limited flu-like disease, whereas the icteric form is a severe illness characterized by multiple organ involvement or even failure. A case involving a patient with rapidly progressing renal insufficiency requiring intermittent renal replacement therapy due to Leptospira grippotyphosa in the absence of a Weil’s disease is reported.
Acute interstitial nephritis; Leptospira grippotyphosa; Morbus Weil
A case of cutaneous Mycobacterium marinum infection acquired from Artemia nyos (sea monkeys) is presented. The infection was unresponsive to initial antimicrobial therapies. A biopsy of a lesion revealed granulomatous inflammation with cultures that subsequently grew M marinum. A three-month course of clarithromycin provided complete resolution.
Brine shrimp; Fish tank granuloma; Mycobacterium marinum
Bacillus cereus is a common cause of gastrointestinal diseases. The majority of individuals with B cereus-related food poisoning recover without any specific treatment. It can, however, rarely cause invasive disease in immunocompromised patients.
Bacillus cereus; Food poisoning; Septicemia, Rhabdomyolysis
Studies have found that Aboriginal people living with HIV/AIDS (APHAs) are more likely than non-APHAs to receive suboptimal HIV care, yet achieve similar clinical outcomes with proper care.
To compare the proportions of individuals diagnosed late with HIV between APHAs and non-APHAs within the Ontario HIV Treatment Network Cohort Study (OCS).
The analysis included OCS participants who completed the baseline visit by November 2009. Two definitions of the outcome of late HIV diagnosis were used: the proportion of participants with an AIDS-defining illness (ADI) before or within three months of HIV diagnosis; and the proportion of participants with a CD4+ count <200 cells/mL at diagnosis. Logistic regression analysis was used to assess the association between Aboriginal ethnicity and late HIV diagnosis.
APHAs were more likely to be female and have lower income, education and employment. No statistically significant differences were noted in the proportions receiving a late HIV diagnosis defined by ADI (Aboriginal 5.2% versus non-Aboriginal 6.3%; P=0.40). Multivariate logistic regression analysis revealed a significant association between Aboriginal ethnicity and late HIV diagnosis defined by CD4+ count after adjusting for age and HIV risk factor (OR 1.55; P=0.04).
APHAs were more likely to have a CD4+ count <200 cells/mL at diagnosis but had similar clinical outcomes from late diagnosis when defined by ADI. However, differences may be underestimated due to recruitment limitations and selection bias.
Additional work is needed to address the socioeconomic and health care needs of APHAs.
Aboriginal peoples; Access to care; Cohort study; HIV; HIV diagnosis; Quality of care
Necrotizing enterocolitis (NEC) is the most common gastrointestinal disease in neonatal intensive care units. Although the pathogenesis of NEC remains unclear, evidence suggests that infections, especially bacterial infections, may play an important role. Viral infections may also result in NEC. Several outbreaks of NEC associated with rotaviruses have been described previously.
To investigate the association between rotavirus (RV) and serum interleukin (IL)-6 and IL-8 levels in infants with NEC.
RV infections were prospectively studied using antigen detection in the stools of 31 infants with NEC. Additionally, serum levels of IL-6, IL-8 and tumour necrosis factor-alpha were tested using micro-ELISA at 0 h and 48 h after diagnosis of NEC.
Fecal specimens from 13 infants were positive, while fecal specimens from 18 infants were negative for RV according to antigen detection (RV+ and RV− groups, respectively). The mortality rate and the severity of NEC were not significantly different between the RV+ and RV− groups. IL-6 levels at 0 h and 48 h after diagnosis of NEC in RV+ infants were lower compared with RV− infants, while IL-8 levels were greater at 0 h and 48 h after diagnosis of NEC in RV+ infants compared with RV− infants.
A high prevalence of RV infection in neonates with NEC was found. Decreased IL-6 levels and increased IL-8 and tumour necrosis factor-alpha levels in RV+ neonates with NEC suggests a role for RV in NEC.
Cytokines; Necrotizing enterocolitis; Rotavirus
The present article addresses the use of antiviral drugs in the management of seasonal influenza illness for the 2012/2013 season. It updates the previous document published in 2011 (1). Noteworthy guidance updates since 2011 include the following:
Seasonal influenza in 2012/2013 is predicted to be caused by two human influenza A and one influenza B strain, all of which are anticipated to remain generally susceptible to oseltamivir.The predicted strains are A/California/7/2009 (H1N1) pdm09-like, A/Victoria/361/2011 (H3N2)-like and B/Wisconsin/1/2010-like (Yamagata lineage). All are included in the seasonal influenza vaccine and are susceptible to oseltamivir.Swine-variant H3N2v, which has rarely caused infection in humans exposed to infected swine within the past year in the United States, is susceptible to oseltamivir. It is not included in the current seasonal influenza vaccine.It is still considered that initiation of antiviral therapy more than 36 h to 48 h after onset of symptoms is beneficial in patients hospitalized with complicated influenza and severe illness.Oseltamivir continues to be recommended for the treatment of influenza in pregnant women.The use of antiviral drugs among measures to control outbreaks of influenza in closed facilities such as correctional institutions is now included in the present document.