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1.  Variability of Infectious Aerosols Produced during Coughing by Patients with Pulmonary Tuberculosis 
Rationale: Mycobacterium tuberculosis is transmitted by infectious aerosols, but assessing infectiousness currently relies on sputum microscopy that does not accurately predict the variability in transmission.
Objectives: To evaluate the feasibility of collecting cough aerosols and the risk factors for infectious aerosol production from patients with pulmonary tuberculosis (TB) in a resource-limited setting.
Methods: We enrolled subjects with suspected TB in Kampala, Uganda and collected clinical, radiographic, and microbiological data in addition to cough aerosol cultures. A subset of 38 subjects was studied on 2 or 3 consecutive days to assess reproducibility.
Measurements and Main Results: M. tuberculosis was cultured from cough aerosols of 28 of 101 (27.7%; 95% confidence interval [CI], 19.9–37.1%) subjects with culture-confirmed TB, with a median 16 aerosol cfu (range, 1–701) in 10 minutes of coughing. Nearly all (96.4%) cultivable particles were 0.65 to 4.7 μm in size. Positive aerosol cultures were associated with higher Karnofsky performance scores (P = 0.016), higher sputum acid-fast bacilli smear microscopy grades (P = 0.007), lower days to positive in liquid culture (P = 0.004), stronger cough (P = 0.016), and fewer days on TB treatment (P = 0.047). In multivariable analyses, cough aerosol cultures were associated with a salivary/mucosalivary (compared with purulent/mucopurulent) appearance of sputum (odds ratio, 4.42; 95% CI, 1.23–21.43) and low days to positive (per 1-d decrease; odds ratio, 1.17; 95% CI, 1.07–1.33). The within-test (kappa, 0.81; 95% CI, 0.68–0.94) and interday test (kappa, 0.62; 95% CI, 0.43–0.82) reproducibility were high.
Conclusions: A minority of patients with TB (28%) produced culturable cough aerosols. Collection of cough aerosol cultures is feasible and reproducible in a resource-limited setting.
doi:10.1164/rccm.201203-0444OC
PMCID: PMC3443801  PMID: 22798319
tuberculosis; cough; air microbiology; infectious disease transmission; infection control
2.  The effect of anthelminthic treatment during pregnancy on HIV plasma viral load; results from a randomised, double blinded, placebo-controlled trial in Uganda 
Background
To investigate the effect of helminth infections and their treatment during pregnancy on HIV load, we conducted a 2×2 factorial randomised controlled trial of albendazole versus placebo and praziquantel versus placebo in pregnant women in Entebbe, Uganda
Methods
Two hundred and sixty-four HIV-infected women from the Entebbe Mother and Baby Study (ISRCTN32849447) were included in this analysis. Women were tested for helminth infections at enrolment and mean HIV load was compared between infected and uninfected groups. The effect of anthelminthic treatment on HIV load was evaluated at six weeks post-treatment and at delivery using linear regression and adjusting for enrolment viral load.
Results
Hookworm and Trichuris infections were associated with higher mean viral load at enrolment (adjusted mean difference 0.24log10 copies/ml, 95% confidence interval (CI): 0.01 to 0.47, p=0.03 and 0.37log10 copies/ml, 95%CI: 0.00 to 0.74, p=0.05, respectively). There were no associations between viral load and other helminth species. There was some evidence that albendazole reduced viral load at six weeks post-treatment (adjusted mean difference −0.17, 95% CI: −0.36 to 0.01, p=0.07), however this effect did not differ according to mother’s hookworm infection status and had diminished at delivery (adjusted mean difference −0.11, 95% CI: −0.28 to 0.07, p=0.23). There was no effect of praziquantel treatment on HIV load at any time point.
Conclusions
Infection with some soil-transmitted helminth species is associated with increased HIV load in pregnancy. Treatment with albendazole causes a small decrease in HIV load, however this may not represent a direct effect of worm removal.
doi:10.1097/QAI.0b013e3182511e42
PMCID: PMC3383620  PMID: 22728750
HIV; viral load; helminths; anthelminthic treatment; clinical trial
3.  Long-Lived Memory B-Cell Responses following BCG Vaccination 
PLoS ONE  2012;7(12):e51381.
The role of T-cells in immunity against Mycobacterium tuberculosis (M. tuberculosis) infection has been extensively studied, however, that of B-cells still remains comparatively unexplored. In this study, we determined the presence and frequencies of mycobacteria-specific memory B-cells (MBCs) in peripheral blood from clinically healthy, Bacillus Calmette Guerin (BCG) vaccinated (n = 79) and unvaccinated (n = 14) donors. Purified protein derivative (PPD)-specific MBCs were present in most donors (both vaccinated and unvaccinated) but their frequencies were significantly higher in vaccinated than in unvaccinated donors. MBCs specific for other mycobacterial antigens [antigen-85A (Ag85A), antigen-85B (Ag85B), 6 kDalton early secretory antigenic target (ESAT-6) and the 10 kDalton-culture filtrate protein (CFP-10)] were less prevalent than those recognising PPD. Furthermore, PPD-specific MBCs were detected in BCG vaccinated donors without ESAT-6 and CFP-10 specific responses. Together, these results indicate that BCG vaccination induces long-lived MBC responses. Similar patterns of response were seen when we examined mycobacteria-specific antibody and T-cell responses in these donors. Our data show for the first time that BCG vaccination elicits long-lived mycobacteria-specific MBC responses in healthy individuals, suggesting a more substantial role of B-cells in the response to BCG and other mycobacterial infections than previously thought.
doi:10.1371/journal.pone.0051381
PMCID: PMC3519837  PMID: 23240017
4.  Impact of Anthelminthic Treatment in Pregnancy and Childhood on Immunisations, Infections and Eczema in Childhood: A Randomised Controlled Trial 
PLoS ONE  2012;7(12):e50325.
Background
Helminth infections may modulate immune responses to unrelated pathogens and allergens; these effects may commence prenatally. We addressed the hypothesis that anthelminthic treatment in pregnancy and early childhood would improve responses to immunisation and modulate disease incidence in early childhood with both beneficial and detrimental effects.
Methods and Findings
A randomised, double-blind, placebo-controlled trial was conducted in Entebbe, Uganda [ISRCTN32849447]. In three independent randomisations, 2507 pregnant women were allocated to receive single-dose albendazole or placebo, and praziquantel or placebo; 2016 of their offspring were randomised to receive quarterly single-dose albendazole or placebo from age 15 months to 5 years. Primary outcomes were post-immunisation recall responses to BCG and tetanus antigens, and incidence of malaria, diarrhoea, and pneumonia; incidence of eczema was an important secondary outcome. Analysis was by intention-to-treat. Of 2345 live births, 1622 (69%) children remained in follow-up at age 5 years. 68% of mothers at enrolment, and 11% of five-year-olds, had helminth infections. Maternal hookworm and Schistosoma mansoni were effectively treated by albendazole and praziquantel, respectively; and childhood hookworm and Ascaris by quarterly albendazole. Incidence rates of malaria, diarrhoea, pneumonia, and eczema were 34, 65, 10 and 5 per 100 py, respectively. Albendazole during pregnancy caused an increased rate of eczema in the children (HR 1.58 (95% CI 1.15–2.17), p = 0.005). Quarterly albendazole during childhood was associated with reduced incidence of clinical malaria (HR 0.85 (95% CI 0.73–0.98), p = 0.03). There were no consistent effects of the interventions on any other outcome.
Conclusions
Routine use of albendazole in pregnancy may not always be beneficial, even in tropical developing countries. By contrast, regular albendazole treatment in preschool children may have an additional benefit for malaria control where helminths and malaria are co-endemic. Given the low helminth prevalence in our children, the effect of albendazole on malaria is likely to be direct.
Trial registration
Current Controlled Trials ISRCTN32849447
doi:10.1371/journal.pone.0050325
PMCID: PMC3517620  PMID: 23236367
5.  Determining Mycobacterium tuberculosis Infection among BCG-Immunised Ugandan Children by T-SPOT.TB and Tuberculin Skin Testing 
PLoS ONE  2012;7(10):e47340.
Background
Children with latent tuberculosis infection (LTBI) represent a huge reservoir for future disease. We wished to determine Mycobacterium tuberculosis (M.tb) infection prevalence among BCG-immunised five-year-old children in Entebbe, Uganda, but there are limited data on the performance of immunoassays for diagnosis of tuberculosis infection in children in endemic settings. We therefore evaluated agreement between a commercial interferon gamma release assay (T-SPOT.TB) and the tuberculin skin test (TST; 2 units RT-23 tuberculin; positive defined as diameter ≥10 mm), along with the reproducibility of T-SPOT.TB on short-term follow-up, in this population.
Methodology/Principal Findings
We recruited 907 children of which 56 were household contacts of TB patients. They were tested with T-SPOT.TB at age five years and then re-examined with T-SPOT.TB (n = 405) and TST (n = 319) approximately three weeks later. The principal outcome measures were T-SPOT.TB and TST positivity. At five years, 88 (9.7%) children tested positive by T-SPOT.TB. More than half of those that were T-SPOT.TB positive at five years were negative at follow-up, whereas 96% of baseline negatives were consistently negative. We observed somewhat better agreement between initial and follow-up T-SPOT.TB results among household TB contacts (κ = 0.77) than among non-contacts (κ = 0.39). Agreement between T-SPOT.TB and TST was weak (κ = 0.28 and κ = 0.40 for T-SPOT.TB at 5 years and follow-up, respectively). Of 28 children who were positive on both T-SPOT.TB tests, 14 (50%) had a negative TST. Analysis of spot counts showed high levels of instability in responses between baseline and follow-up, indicating variability in circulating numbers of T cells specific for certain M.tb antigens.
Conclusions/Significance
We found that T-SPOT.TB positives are unstable over a three-week follow-up interval, and that TST compares poorly with T-SPOT.TB, making the categorisation of children as TB-infected or TB-uninfected difficult. Existing tools for the diagnosis of TB infection are unsatisfactory in determining infection among children in this setting.
doi:10.1371/journal.pone.0047340
PMCID: PMC3471887  PMID: 23077594
6.  Incongruous consultation behaviour: results from a UK-wide population survey 
BMC Family Practice  2012;13:21.
Background
Symptom characteristics are strong drivers of care seeking. Despite this, incongruous consultation behaviour occurs and has implications for both individuals and health-care services. The aim of this study was to determine how frequently incongruous consultation behaviour occurs, to examine whether it is more common for certain types of symptoms and to identify the factors associated with being an incongruous consulter.
Methods
An age and sex stratified random sample of 8,000 adults was drawn from twenty UK general practices. A postal questionnaire was used to collect detailed information on the presence and characteristics of 25 physical and psychological symptoms, actions taken to manage the symptoms, general health, attitudes to symptom management and demographic/socio-economic details. Two types of incongruous consultation behaviour were examined: i) consultation with a GP for symptoms self-rated as low impact and ii) no consultation with a GP for symptoms self-rated as high impact.
Results
A fifth of all symptoms experienced resulted in consultation behaviour which was incongruous based on respondents' own rating of the symptoms' impact. Low impact consultations were not common, although symptoms indicative of a potentially serious condition resulted in a higher proportion of low impact consultations. High impact non-consultations were more common, although there was no clear pattern in the type of associated symptoms. Just under half of those experiencing symptoms in the previous two weeks were categorised as an incongruous consulter (low impact consulter: 8.3%, high impact non-consulter: 37.1%). Employment status, having a chronic condition, poor health, and feeling that reassurance or advice from a health professional is important were associated with being a low impact consulter. Younger age, employment status, being an ex-smoker, poor health and feeling that not wasting the GPs time is important were associated with being a high impact non-consulter.
Conclusions
This is one of the first studies to examine incongruous consultation behaviour for a range of symptoms. High impact non-consultations were common and may have important health implications, particularly for symptoms indicative of serious disease. More research is now needed to examine incongruous consultation behaviour and its impact on both the public's health and health service use.
doi:10.1186/1471-2296-13-21
PMCID: PMC3338366  PMID: 22433072
Signs & symptoms; Community-based; Health care services; Primary care
7.  The influence of BCG vaccine strain on mycobacteria-specific and non-specific immune responses in a prospective cohort of infants in Uganda 
Vaccine  2012;30(12):2083-2089.
Highlights
► Largest study comparing BCG strains and first to assess strain effects on non-specific responses. ► Cytokine responses to both mycobacterial and non-mycobacterial stimuli are strain-dependent. ► BCG-Denmark causes higher cytokine levels and more scars and adverse events than two other strains. ► Sex may interact with the effect of strain; non-specific responses are not associated with scars. ► BCG strain choice may be important and should be evaluated in novel vaccine strategies using BCG.
Background
Globally, BCG vaccination varies in efficacy and has some non-specific protective effects. Previous studies comparing BCG strains have been small-scale, with few or no immunological outcomes and have compared TB-specific responses only. We aimed to evaluate both specific and non-specific immune responses to different strains of BCG within a large infant cohort and to evaluate further the relationship between BCG strain, scarring and cytokine responses.
Methods
Infants from the Entebbe Mother and Baby Study (ISRCTN32849447) who received BCG-Russia, BCG-Bulgaria or BCG-Denmark at birth, were analysed by BCG strain group. At one year, interferon-gamma (IFN-γ), interleukin (IL)-5, IL-13 and IL-10 responses to mycobacteria-specific antigens (crude culture filtrate proteins and antigen 85) and non-mycobacterial stimuli (tetanus toxoid and phytohaemagglutinin) were measured using ELISA. Cytokine responses, scar frequency, BCG associated adverse event frequency and mortality rates were compared across groups, with adjustments for potential confounders.
Results
Both specific and non-specific IFN-γ, IL-13 and IL-10 responses in 1341 infants differed between BCG strain groups including in response to stimulation with tetanus toxoid. BCG-Denmark immunised infants showed the highest cytokine responses. The proportion of infants who scarred differed significantly, with BCG scars occurring in 52.2%, 64.1% and 92.6% of infants immunised with BCG Russia, BCG-Bulgaria and BCG-Denmark, respectively (p < 0.001). Scarred infants had higher IFN-γ and IL-13 responses to mycobacterial antigens only than infants without a scar. The BCG-Denmark group had the highest frequency of adverse events (p = 0.025). Mortality differences were not significant.
Conclusions
Both specific and non-specific immune responses to the BCG vaccine differ by strain. Scarring after BCG vaccination is also strain-dependent and is associated with higher IFN-γ and IL-13 responses to mycobacterial antigens. The choice of BCG strain may be an important factor and should be evaluated when testing novel vaccine strategies that employ BCG in prime–boost sequences, or as a vector for other vaccine antigens.
doi:10.1016/j.vaccine.2012.01.053
PMCID: PMC3314967  PMID: 22300718
BCG; Strain; Immune response; Non-specific effects; BCG scar
8.  Maternal recall of birthweight and birth size in Entebbe, Uganda 
Objectives
To assess the reliability of maternally recalled birthweight and size in Entebbe, Uganda.
Methods
The study population comprised 404 mothers, who were participants in the Entebbe Mother and Baby Study (EMaBS). Mothers were recruited to EMaBS during antenatal care, maternal characteristics were recorded during pregnancy, and birthweight was recorded at delivery. Four to seven years after delivery, mothers were asked to recall the child’s birthweight and size. Their responses were compared with the birthweight recorded in the EMaBS database.
Results
Of 404 interviewed mothers, 303 (75%) were able to give an estimate of birthweight and for 265 of these EMaBS data on recorded birthweights were available. Women who were educated and whose children had low birth order were more likely to be able to give an estimate: 37 (14%) recalled the exact recorded birthweight; a further 52 (20%) were accurate to within 0.1 kg of the recorded weight. On average, mothers overestimated birthweight by 0.06 kg (95% CI: 0.00–0.13 kg, P = 0.04). Recalled and recorded birthweights showed moderate agreement with an intraclass correlation coefficient of 0.64. Four hundered mothers gave an estimate of birth size: the sensitivity and specificity of recalled birth size for classifying low birthweight were 76% (95% CI: 50–93%) and 70% (95% CI: 65–75%), respectively.
Conclusions
Mothers’ recall of birthweight was not precise but in absence of other data, recall of birthweight and size may have some value in epidemiological studies in these settings.
doi:10.1111/j.1365-3156.2012.03091.x
PMCID: PMC3627817  PMID: 22994260
birthweight; reliability; validity; uganda
9.  Effects of Maternal Worm Infections and Anthelminthic Treatment during Pregnancy on Infant Motor and Neurocognitive Functioning 
We tested the hypothesis that maternal worm infections in pregnancy affect infant motor and neurocognitive development, and that anthelminthic treatment during pregnancy can reverse these effects. We used measures which examine infant motor, cognitive and executive function, including inhibition. We assessed 983 Ugandan infants aged 15 months, using locally appropriate measures within the Entebbe Mother and Baby Study, a trial of anthelminthic treatment during pregnancy. Key exposures were maternal worm infections and anthelminthic treatment during pregnancy. Effects of other health and social factors were controlled for statistically. Of the five major worm species found in the pregnant women, two had influences on the developmental measures: Maternal Mansonella perstans and Strongyloides stercoralis infections showed negative associations with the A-not B-task, and Language, respectively. Performance on other psychomotor and cognitive measures was associated with illnesses during infancy and infants’ behavior during assessment, but not with maternal worm infections. There were no positive effects of maternal anthelminthic treatment on infant abilities. Mansonella perstans and Strongyloides stercoralis infection during pregnancy seem associated with impaired early executive function and language, respectively, but single-dose anthelminthic treatment during pregnancy was not beneficial. The biological mechanisms that could underlie these neurocognitive effects are discussed. (JINS, 2012, 18, 1019–1030)
doi:10.1017/S1355617712000768
PMCID: PMC3948080  PMID: 23158229
Pregnancy; Helminths; De-worming; Infancy; Psychomotor; Executive function

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