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1.  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
2.  Effects of maternal and infant co-infections, and of maternal immunisation, on the infant response to BCG and tetanus immunisation 
Vaccine  2010;29(2-2):247-255.
Some vaccines show poor efficacy in tropical countries. Within a birth cohort in Uganda, we investigated factors that might influence responses to BCG and tetanus immunisation. Whole blood assay responses to crude culture filtrate proteins of Mycobacterium tuberculosis (cCFP)) and tetanus toxoid (TT) were examined among 1506 and 1433 one-year-olds, respectively. Maternal Mansonella perstans infection was associated with higher interleukin (IL)-10 responses to both immunogens but no reduction in gamma interferon (IFN-γ), IL-5 and IL-13 responses; other maternal helminth infections showed little effect. Tetanus immunisation during pregnancy was associated with higher infant responses to TT; maternal BCG scar (from past immunisation) with lower infant IL-5 and IL-13 responses to cCFP. IFN-γ, IL-5 and IL-13 to TT were reduced in HIV-exposed-uninfected infants; infant malaria and HIV were associated with lower IFN-γ, IL-5 and IL-13 responses to both immunogens. We conclude that maternal helminth infections are unlikely to explain poor vaccine efficacy in the tropics. Effects of maternal immunisation on infant responses to vaccines should be explored. Prevention of infant malaria and HIV could contribute to effectiveness of immunisation programmes.
doi:10.1016/j.vaccine.2010.10.047
PMCID: PMC3021124  PMID: 21040693
BCG; Tetanus; Immunisation
3.  Plasmodium falciparum and helminth co-infection in a semi-urban population of pregnant women in Uganda 
The Journal of infectious diseases  2008;198(6):920-927.
Introduction
Helminth infections and malaria are widespread in the tropics. Recent studies suggest helminth infections may increase susceptibility to malaria. If confirmed, this could be particularly important during pregnancy-induced immunosuppression.
Aim
To evaluate the geographical distribution of Plasmodium falciparum-helminth co-infection, and associations between parasite species in pregnant women in Entebbe, Uganda.
Methods
A cross-sectional study was conducted at baseline in a trial of anti-helminthics during pregnancy. Helminth and P.falciparum infections were quantified in 2507 asymptomatic women; socio-demographic and geographical details were recorded.
Results
Hookworm and Mansonella perstans were associated with P.falciparum but the effect of hookworm was seen only in the absence of M.perstans (OR for P.falciparum, adjusted for age, tribe, socioeconomic status, HIV and location: hookworm without M.perstans 1.53 (95% CI 1.09-2.14); M.perstans without hookworm 2.33 (1.47-3.69), both hookworm and M.perstans, 1.85 (1.24-2.76)). No association was observed between Schistosoma mansoni, Trichuris or Strongyloides and P.falciparum.
Conclusions
Hookworm-P.falciparum and M.perstans-P.falciparum co-infection amongst pregnant women in Entebbe is more common than expected by chance. Further studies are needed to elucidate the mechanism of this association. Helminth-induced increased susceptibility to P.falciparum could have important consequences for pregnancy outcome and responses to malaria in infancy.
doi:10.1086/591183
PMCID: PMC2886962  PMID: 18721060
Malaria; Helminth; Hookworm; Mansonella perstans; Plasmodium falciparum; Co-Infection; Spatial; Geographic Factors; Pregnancy; Uganda
4.  The impact of helminths on the response to immunization and on the incidence of infection and disease in childhood in Uganda: design of a randomized, double-blind, placebo-controlled, factorial trial of deworming interventions delivered in pregnancy and early childhood [ISRCTN32849447] 
Background
Helminths have profound effects on the immune response, allowing long-term survival of parasites with minimal damage to the host. Some of these effects "spill-over", altering responses to non-helminth antigens or allergens. It is suggested that this may lead to impaired responses to immunizations and infections, while conferring benefits against inflammatory responses in allergic and autoimmune disease. These effects might develop in utero, through exposure to maternal helminth infections, or through direct exposure in later life.
Purpose
To determine the effects of helminths and their treatment in pregnancy and in young children on immunological and disease outcomes in childhood.
Methods
The trial has three randomized, double-blind, placebo-controlled interventions at two times, in two people: a pregnant woman and her child. Pregnant women are randomized to albendazole or placebo and praziquantel or placebo. At age 15 months their children are randomized to three-monthly albendazole or placebo, to continue to age five years. The proposed designation for this sequence of interventions is a 2 X 2(x2) factorial design.
Children are immunized with BCG and against polio, Diphtheria, tetanus, Pertussis, Haemophilus, hepatitis B and measles. Primary immunological outcomes are responses to BCG antigens and tetanus toxoid in whole blood cytokine assays and antibody assays at one, three and five years of age. Primary disease outcomes are incidence of malaria, pneumonia, diarrhoea, tuberculosis, measles, vertical HIV transmission, and atopic disease episodes, measured at clinic visits and twice-monthly home visits. Effects on anaemia, growth and intellectual development are also assessed.
Conclusion
This trial, with a novel design comprising related interventions in pregnant women and their offspring, is the first to examine effects of helminths and their treatment in pregnancy and early childhood on immunological, infectious disease and allergic disease outcomes. The results will enhance understanding of both detrimental and beneficial effects of helminth infection and inform policy. Clinical Trials 2007; 4: 42–57. http://ctj.sagepub.com
doi:10.1177/1740774506075248
PMCID: PMC2643383  PMID: 17327245
5.  Use of antenatal services and delivery care in Entebbe, Uganda: a community survey 
Background
Disparities in perinatal health care occur worldwide. If the UN Millennium Development Goals in maternal and child health are to be met, this needs to be addressed. This study was conducted to facilitate our understanding of the changing use of maternity care services in a semi-urban community in Entebbe Uganda and to examine the range of antenatal and delivery services received in health care facilities and at home.
Methods
We conducted a retrospective community survey among women using structured questionnaires to describe the use of antenatal services and delivery care.
Results
In total 413 women reported on their most recent pregnancy. Antenatal care attendance was high with 96% attending once, and 69% the recommended four times. Blood pressure monitoring (95%) and tetanus vaccination (91%) were the services most frequently reported and HIV testing (47%), haematinics (58%) and presumptive treatment for malaria (66%) least frequently. Hospital clinics significantly outperformed public clinics in the quality of antenatal service. A significant improvement in the reported quality of antenatal services received was observed by year (p < 0.001). Improvement in the range and consistency of services at Entebbe Hospital over time was associated with an increase in the numbers who sought care there (p = 0.038). Although 63% delivered their newborn at a local hospital, 11% still delivered at home with no skilled assistance and just under half of these women reported financial/transportation difficulties as the primary reason. Less educated, poorer mothers were more likely to have unskilled/no assistance. Simple newborn care practices were commonly neglected. Only 35% of newborns were breastfed within the first hour and delayed wrapping of newborn infants occurred after 27% of deliveries.
Conclusion
Although antenatal services were well utilised, the quality of services varied. Women were able and willing to travel to a facility providing a good service. Access to essential skilled birth attendants remains difficult especially for less educated, poorer women, commonly mediated by financial and transport difficulties and several simple post delivery practices were commonly neglected. These factors need to be addressed to ensure that high quality care reaches the most vulnerable women and infants.
doi:10.1186/1471-2393-7-23
PMCID: PMC2098779  PMID: 17931422
6.  Maternal HIV infection and other factors associated with growth outcomes of HIV-uninfected infants in Entebbe, Uganda 
Public Health Nutrition  2013;16(9):1548-1557.
Objective
To assess the associations between maternal HIV infection and growth outcomes of HIV-exposed but uninfected infants and to identify other predictors for poor growth among this population.
Design
Within a trial of de-worming during pregnancy, the cohort of offspring was followed from birth. HIV status of the mothers and their children was investigated and growth data for children were obtained at age 1 year. Length-for-age, weight-for-age and weight-for-length Z-scores were calculated for each child; Z-scores <−2 were defined as stunting, underweight and wasting, respectively.
Setting
The study was conducted in Entebbe municipality and Katabi sub-county, Uganda.
Subjects
The sample consisted of 1502 children aged 1 year: HIV-unexposed (n 1380) and HIV-exposed not infected (n 122).
Results
Prevalence of stunting, underweight and wasting was 14·2 %, 8·0 % and 3·9 %, respectively. There was evidence for an association between maternal HIV infection and odds of being underweight (adjusted OR = 2·32; 95 % CI 1·32, 4·09; P = 0·006) but no evidence for an association with stunting or with wasting. Young maternal age, low maternal education, low birth weight, early weaning and experiencing a higher number of episodes of malaria during infancy were independent predictors for stunting and underweight. A higher number of living children in the family was associated with wasting.
Conclusions
Maternal HIV infection was associated with being underweight in HIV-exposed uninfected infants. The success of programmes for prevention of mother-to-child HIV transmission means that an increasing number of infants will be born to HIV-infected women without acquiring HIV. Therefore, viable nutritional interventions need to be identified for this population.
doi:10.1017/S1368980013000499
PMCID: PMC3733066  PMID: 23507372
HIV exposure; Poor growth; Infancy; Uganda
7.  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
8.  Effect of single-dose anthelmintic treatment during pregnancy on an infant's response to immunisation and on susceptibility to infectious diseases in infancy: a randomised, double-blind, placebo-controlled trial 
Lancet  2011;377(9759):52-62.
Summary
Background
Helminth infections affect the human immune response. We investigated whether prenatal exposure to and treatment of maternal helminth infections affects development of an infant's immune response to immunisations and unrelated infections.
Methods
In this randomised, double-blind, placebo-controlled trial, we enrolled 2507 women in the second or third trimester of pregnancy who were planning to deliver in Entebbe General Hospital, Entebbe, Uganda. With a computer-generated random number sequence in blocks of 100, we assigned patients to 440 mg albendazole and 40 mg/kg praziquantel (n=628), 440 mg albendazole and a praziquantel-matching placebo (n=625), 40 mg/kg praziquantel and an albendazole-matching placebo (n=626), or an albendazole-matching placebo and praziquantel-matching placebo (n=628). All participants and hospital staff were masked to allocation. Primary outcomes were immune response at age 1 year to BCG, tetanus, and measles immunisation; incidence of infectious diseases during infancy; and vertical HIV transmission. Analysis was by intention-to-treat. This trial is registered, number ISRCTN32849447.
Findings
Data were available at delivery for 2356 women, with 2345 livebirths; 2115 (90%) of liveborn infants remained in follow-up at 1 year of age. Neither albendazole nor praziquantel treatments affected infant response to BCG, tetanus, or measles immunisation. However, in infants of mothers with hookworm infection, albendazole treatment reduced interleukin-5 (geometric mean ratio 0·50, 95% CI 0·30–0·81, interaction p=0·02) and interleukin-13 (0·52, 0·34–0·82, 0·0005) response to tetanus toxoid. The rate per 100 person-years of malaria was 40·9 (95% CI 38·3–43·7), of diarrhoea was 134·1 (129·2–139·2), and of pneumonia was 22·3 (20·4–24·4). We noted no effect on infectious disease incidence for albendazole treatment (malaria [hazard ratio 0·95, 95% CI 0·79–1.14], diarrhoea [1·06, 0·96–1·16], pneumonia [1·11, 0·90–1·38]) or praziquantel treatment (malaria [1·00, 0·84–1·20], diarrhoea [1·07, 0·98–1·18], pneumonia [1·00, 0·80–1·24]). In HIV-exposed infants, 39 (18%) were infected at 6 weeks; vertical transmission was not associated with albendazole (odds ratio 0·70, 95% CI 0·35–1·42) or praziquantel (0·60, 0·29–1·23) treatment.
Interpretation
These results do not accord with the recently advocated policy of routine antenatal anthelmintic treatment, and the value of such a policy may need to be reviewed.
Funding
Wellcome Trust.
doi:10.1016/S0140-6736(10)61457-2
PMCID: PMC3018567  PMID: 21176950

Results 1-8 (8)