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Abstract Background Over 1 billion of the world's poorest inhabitants are afflicted by neglected tropical diseases (NTDs). Integrated control programmes aimed at tackling these debilitating NTDs have been recently initiated, mainly using preventative chemotherapy. Monitoring and evaluation (M&E) of these integrated programs presents particular challenges over and above those required for single disease vertical programmes. We used baseline data from the National NTD Control Programme in Burkina Faso in order to assess the feasibility of an integrated survey design, as well as to elucidate the contribution of environmental variables to the risk of either Schistosoma haematobium, trachoma, or both among school-aged children. Methods S. haematobium infection was diagnosed by detecting eggs in urine. A trachoma case was defined by the presence of Trachomatous inflammation-Follicular (TF) and/or Trachomatous inflammation-Intense (TI) in either eye. Baseline data collected from 3,324 children aged 7-11 years in 21 sentinel sites across 11 regions of Burkina Faso were analyzed using simple and multivariable hierarchical binomial logistic regression models fitted by Markov Chain Monte Carlo estimation methods. Probabilities of the risk of belonging to each infection/disease category were estimated as a function of age, gender (individual level), and environmental variables (at sentinel site level, interpolated from national meteorological stations). Results Overall prevalence at the sentinel sites was 11.79% (95% CI: 10.70-12.89) for S. haematobium; 13.30% (12.14-14.45) for trachoma and 0.84% (0.53-1.15) for co-infections. The only significant predictor of S. haematobium infection was altitude. There were significant negative associations between the prevalence of active trachoma signs and minimum temperature, and air pressure. Conditional upon these predictors, these data are consistent with the two pathogens being independent. Conclusions Urogenital schistosomiasis and trachoma constitute public health problems in Burkina Faso. Sentinel site (at school level) surveys for these two NTDs can be implemented simultaneously. However, to support MDA treatment decisions in Burkina Faso, the protocol used in this study would only be applicable to hypoendemic trachoma areas. More research is needed to confirm if these findings can be generalized to West Africa and beyond.

Abstract Background In the developing world co-infections and polyparasitism within humans appear to be the rule rather than the exception, be it any combination of inter-specific and/or inter- and intra-Genera mixed infections. Mixed infections might generate synergistic or antagonistic interactions and thereby clinically affect individuals and/or impact parasite epidemiology. Methods The current study uniquely assesses both Schistosoma mansoni- and Schistosoma haematobium-related morbidity of the liver and the bladder as assessed by ultrasound as well as spleen and liver morbidity through clinical exams. The impact of praziquantel (PZQ) treatment on such potential inter-specific schistosome interactions and resulting morbidity using uniquely detailed longitudinal data (pre- and one year post-PZQ treatment) arising from the National Schistosomiasis Control Program in three areas of Mali: Ségou, Koulikoro and Bamako, is also evaluated. At baseline, data were collected from up to 2196 children (aged 7-14 years), 844 of which were infected with S. haematobium only, 124 with S. mansoni only and 477 with both. Follow-up data were collected from up to 1265 children. Results Results suggested lower liver morbidity in mixed compared to single S. mansoni infections and higher bladder morbidity in mixed compared to single S. haematobium infections. Single S. haematobium or S. mansoni infections were also associated with liver and spleen morbidity whilst only single S. haematobium infections were associated with bladder morbidity in these children (light S. haematobium infection OR: 4.3, p < 0.001 and heavy S. haematobium infection OR: 19, p < 0.001). PZQ treatment contributed to the regression of some of the forms of such morbidities. Conclusions Whilst the precise biological mechanisms for these observations remain to be ascertained, the results illustrate the importance of considering mixed species infections in any analyses of parasite-induced morbidity, including that for the proposed Disability Adjusted Life Years (DALYs) revised estimates of schistosomiasis morbidity.

Abstract Background Schistosomiasis and soil-transmitted helminthiasis (STH) are among the neglected tropical diseases in Africa. A national control program for these diseases was initiated in Uganda during March 2003. Annual treatment with praziquantel and albendazole was given to schoolchildren in endemic areas and to adults in selected communities where local prevalence of Schistosoma mansoni in schoolchildren was high. Methods The impact of the treatment program was monitored through cohorts of schoolchildren and adults. Their infection status with S. mansoni and STH was determined by parasitological examinations at baseline and at annual follow-ups. The prevalence and intensity of S. mansoni and STH before and after treatment were analyzed. Results Two rounds of treatment significantly reduced the prevalence of S. mansoni infection in schoolchildren across three regions in the country from 33.4–49.3% to 9.7–29.6%, and intensity of infection from 105.7–386.8 eggs per gram of faeces (epg) to 11.6–84.1 epg. The prevalence of hookworm infection was reduced from 41.2–57.9% to 5.5–16.1%, and intensity of infection from 186.9–416.8 epg to 3.7–36.9 epg. The proportion of children with heavy S. mansoni infection was significantly reduced from 15% (95% CI 13.4–16.8%) to 2.3% (95% CI 1.6–3.0%). In adults, significant reduction in the prevalence and intensity of S. mansoni and hookworm infections was also observed. More importantly, the prevalence and intensity of both S. mansoni and hookworm infections in the cohorts of newly-recruited 6-year-olds who had never previously received treatment decreased significantly over 2 years: 34.9% (95% CI 31.9–37.8%) to 22.6% (95% CI 19.9–25.2%) and 171.1 epg (95% CI 141.5–200.7) to 72.0 epg (95% CI 50.9–93.1) for S. mansoni; and 48.4% (95% CI 45.4–51.5) to 15.9% (95% CI 13.6–18.2) and 232.7 epg (95% CI 188.4–276.9) to 51.4 epg (95% CI 33.4–69.5) for hookworms, suggesting a general decline in environmental transmission levels. Conclusion Annual anthelminthic treatment delivered to schoolchildren and to adults at high risk in Uganda can significantly reduce the prevalence and intensity of infection for schistosomiasis and STH, and potentially also significantly reduce levels of environmental transmission of infection.

BackgroundGroup B Streptococcus (GBS) can cause invasive disease (iGBS) in young infants, typically presenting as sepsis or meningitis, and is also associated with stillbirth and preterm birth. GBS vaccines are under development, but their potential health impact and cost-effectiveness have not been assessed globally.Methods and findingsWe assessed the health impact and value (using net monetary benefit (NMB), which measures both health and economic effects of vaccination into monetary units) of GBS maternal vaccination in an annual cohort of 140 million pregnant women across 183 countries in 2020. Our analysis uses a decision tree model, incorporating risks of GBS-related health outcomes from an existing Bayesian disease burden model. We extrapolated country-specific GBS-related healthcare costs using data from a previous systematic review and calculated quality-adjusted life years (QALYs) lost due to infant mortality and long-term disability. We assumed 80% vaccine efficacy against iGBS and stillbirth, following the WHO Preferred Product Characteristics, and coverage based on the proportion of pregnant women receiving at least 4 antenatal visits. One dose was assumed to cost $50 in high-income countries, $15 in upper-middle income countries, and $3.50 in low-/lower-middle-income countries. We estimated NMB using alternative normative assumptions that may be adopted by policymakers. Vaccinating pregnant women could avert 127,000 (95% uncertainty range 63,300 to 248,000) early-onset and 87,300 (38,100 to 209,000) late-onset infant iGBS cases, 31,100 deaths (14,400 to 66,400), 17,900 (6,380 to 49,900) cases of moderate and severe neurodevelopmental impairment, and 23,000 (10,000 to 56,400) stillbirths. A vaccine effective against GBS-associated prematurity might also avert 185,000 (13,500 to 407,000) preterm births. Globally, a 1-dose vaccine programme could cost $1.7 billion but save $385 million in healthcare costs. Estimated global NMB ranged from $1.1 billion ($-0.2 to 3.8 billion) under the least favourable normative assumptions to $17 billion ($9.1 to 31 billion) under the most favourable normative assumptions. The main limitation of our analysis was the scarcity of data to inform some of the model parameters such as those governing health-related quality of life and long-term costs from disability, and how these parameters may vary across country contexts.ConclusionsIn this study, we found that maternal GBS vaccination could have a large impact on infant morbidity and mortality. Globally, a GBS maternal vaccine at reasonable prices is likely to be a cost-effective intervention.

Background Group B Streptococcus (GBS) can cause invasive disease (iGBS) in young infants, typically presenting as sepsis or meningitis, and is also associated with stillbirth and preterm birth. GBS vaccines are under development, but their potential health impact and cost-effectiveness have not been assessed globally. Methods and findings We assessed the health impact and value (using net monetary benefit (NMB), which measures both health and economic effects of vaccination into monetary units) of GBS maternal vaccination in an annual cohort of 140 million pregnant women across 183 countries in 2020. Our analysis uses a decision tree model, incorporating risks of GBS-related health outcomes from an existing Bayesian disease burden model. We extrapolated country-specific GBS-related healthcare costs using data from a previous systematic review and calculated quality-adjusted life years (QALYs) lost due to infant mortality and long-term disability. We assumed 80% vaccine efficacy against iGBS and stillbirth, following the WHO Preferred Product Characteristics, and coverage based on the proportion of pregnant women receiving at least 4 antenatal visits. One dose was assumed to cost $50 in high-income countries, $15 in upper-middle income countries, and $3.50 in low-/lower-middle-income countries. We estimated NMB using alternative normative assumptions that may be adopted by policymakers. Vaccinating pregnant women could avert 127,000 (95% uncertainty range 63,300 to 248,000) early-onset and 87,300 (38,100 to 209,000) late-onset infant iGBS cases, 31,100 deaths (14,400 to 66,400), 17,900 (6,380 to 49,900) cases of moderate and severe neurodevelopmental impairment, and 23,000 (10,000 to 56,400) stillbirths. A vaccine effective against GBS-associated prematurity might also avert 185,000 (13,500 to 407,000) preterm births. Globally, a 1-dose vaccine programme could cost $1.7 billion but save $385 million in healthcare costs. Estimated global NMB ranged from $1.1 billion ($-0.2 to 3.8 billion) under the least favourable normative assumptions to $17 billion ($9.1 to 31 billion) under the most favourable normative assumptions. The main limitation of our analysis was the scarcity of data to inform some of the model parameters such as those governing health-related quality of life and long-term costs from disability, and how these parameters may vary across country contexts. Conclusions In this study, we found that maternal GBS vaccination could have a large impact on infant morbidity and mortality. Globally, a GBS maternal vaccine at reasonable prices is likely to be a cost-effective intervention., Author(s): Simon R. Procter 1,2,*, Bronner P. Gonçalves 1,2, Proma Paul 1,2, Jaya Chandna 1,2, Farah Seedat 1,2, Artemis Koukounari 1,2, Raymond Hutubessy 3, Caroline Trotter 4, Joy E. Lawn [...]

Abstract Background In the absence of a consensus on definition and measurement of healthy ageing, we created a healthy ageing index tallying with the functional ability framework provided by the World Health Organization. To create this index, we employed items of functional ability and intrinsic capacity. The current study aims to establish the predictive validity and discrimination properties of this healthy ageing index in settings in Latin American, part of the 10/66 cohort. Methods Population-based cohort studies including 12,865 people ≥65 years old in catchment areas of Cuba, Dominican Republic, Venezuela, Mexico and Peru. We employed latent variable modelling to estimate the healthy ageing scores of each participant. We grouped participants according to the quintiles of the healthy ageing score distribution. Cox’s proportional hazard models for mortality and sub-hazard (competing risks) models for incident dependence (i.e. needing care) were calculated per area after a median of 3.9 years and 3.7 years, respectively. Results were pooled together via fixed-effects meta-analysis. Our findings were compared with those obtained from self-rated health. Results Participants with lowest levels, compared to participants with highest level of healthy ageing, had increased risk of mortality and incident dependence, even after adjusting for sociodemographic and health conditions (HR: 3.25, 95%CI: 2.63–4.02; sub-HR: 5.21, 95%CI: 4.02–6.75). Healthy ageing scores compared to self-rated health had higher population attributable fractions (PAFs) for mortality (43.6% vs 19.3%) and incident dependence (58.6% vs 17.0%), and better discriminative power (Harrell’s c-statistic: mortality 0.74 vs 0.72; incident dependence 0.76 vs 0.70). Conclusion These results provide evidence that our healthy ageing index could be a valuable tool for prevention strategies as it demonstrated predictive and discriminative properties. Further research in other cultural settings will assist moving from a theoretical conceptualisation of healthy ageing to a more practical one.

Abstract Background Our population is ageing and in 2050 more than one out of five people will be 60 years or older; 80% of whom will be living in a low-and-middle income country. Living longer does not entail living healthier; however, there is not a widely accepted measure of healthy ageing hampering policy and research. The World Health Organization defines healthy ageing as the process of developing and maintaining functional ability that will enable well-being in older age. We aimed to create a healthy ageing index (HAI) in a subset of six low-and-middle income countries, part of the 10/66 study, by using items of functional ability and intrinsic capacity. Methods The study sample included residents 65-years old and over (n = 12,865) from catchment area sites in Cuba, Dominican Republic, Peru, Venezuela, Mexico and Puerto Rico. Items were collected by interviewing participants or key informants between 2003 and 2010. Two-stage factor analysis was employed and we compared one-factor, second-order and bifactor models. The psychometric properties of the index, including reliability, replicability, unidimensionality and concurrent convergent validity as well as measurement invariance per ethnic group and gender were further examined in the best fit model. Results The bifactor model displayed superior model fit statistics supporting that a general factor underlies the various items but other subdomain factors are also needed. The HAI indicated excellent reliability (ω = 0.96, ω Η = 0.84), replicability (H = 0.96), some support for unidimensionality (Explained Common Variance = 0.65) and some concurrent convergent validity with self-rated health. Scalar measurement invariance per ethnic group and gender was supported. Conclusions A HAI with excellent psychometric properties was created by using items of functional ability and intrinsic capacity in a subset of six low-and-middle income countries. Further research is needed to explore sub-population differences and to validate this index to other cultural settings.

Sepsis and meningitis due to invasive group B Streptococcus (iGBS) disease during early infancy is a leading cause of child mortality. Recent systematic estimates of the worldwide burden of GBS suggested that there are 319,000 cases of infant iGBS disease each year, and an estimated 147,000 stillbirths and young-infant deaths, with the highest burden occurring in Sub-Saharan Africa. The following priority data gaps were highlighted: (1) long-term outcome data after infant iGBS, including mild disability, to calculate quality-adjusted life years (QALYs) or disability-adjusted life years (DALYs) and (2) economic burden for iGBS survivors and their families. Geographic data gaps were also noted with few studies from low- and middle- income countries (LMIC), where the GBS burden is estimated to be the highest. In this paper we present the protocol for a multi-country matched cohort study designed to estimate the risk of long-term neurodevelopmental impairment (NDI), socioemotional behaviors, and economic outcomes for children who survive invasive GBS disease in Argentina, India, Kenya, Mozambique, and South Africa. Children will be identified from health demographic surveillance systems, hospital records, and among participants of previous epidemiological studies. The children will be aged between 18 months to 17 years. A tablet-based custom-designed application will be used to capture data from direct assessment of the child and interviews with the main caregiver. In addition, a parallel sub-study will prospectively measure the acute costs of hospitalization due to neonatal sepsis or meningitis, irrespective of underlying etiology. In summary, these data are necessary to characterize the consequences of iGBS disease and enable the advancement of effective strategies for survivors to reach their developmental and economic potential. In particular, our study will inform the development of a full public health value proposition on maternal GBS immunization that is being coordinated by the World Health Organization.

Various global health initiatives are currently advocating the elimination of schistosomiasis within the next decade. Schistosomiasis is a highly debilitating tropical infectious disease with severe burden of morbidity and thus operational research accurately evaluating diagnostics that quantify the epidemic status for guiding effective strategies is essential. Latent class models (LCMs) have been generally considered in epidemiology and in particular in recent schistosomiasis diagnostic studies as a flexible tool for evaluating diagnostics because assessing the true infection status (via a gold standard) is not possible. However, within the biostatistics literature, classical LCM have already been criticised for real-life problems under violation of the conditional independence (CI) assumption and when applied to a small number of diagnostics (i.e. most often 3-5 diagnostic tests). Solutions of relaxing the CI assumption and accounting for zero-inflation, as well as collecting partial gold standard information, have been proposed, offering the potential for more robust model estimates. In the current article, we examined such approaches in the context of schistosomiasis via analysis of two real datasets and extensive simulation studies. Our main conclusions highlighted poor model fit in low prevalence settings and the necessity of collecting partial gold standard information in such settings in order to improve the accuracy and reduce bias of sensitivity and specificity estimates.

BackgroundThis paper reports on the baseline prevalence and associated risk factor findings of a pilot, longitudinal study exploring community-wide treatment of schistosomiasis and soil-transmitted helminthiasis, using albendazole plus praziquantel in the Greater Accra region of Ghana.MethodFrom three communities, at least, 658 individuals were enrolled into the study via random household selection. Prevalence and intensity of schistosomiasis and STH infection were determined from stool and urine samples with a questionnaire being administered in order to explore other morbidities and risk factors. Factor analysis of household demographic variables was undertaken to generate a socioeconomic score; this was then further categorised into tertiles. Proportional-odds cumulative logit generalised estimating equation (GEE) models were used to investigate categorical ordinal intensity of infection associations with morbidity. Separately, logistic GEE models were used to investigate risk factor associations with infection prevalence.ResultsBoth Schistosoma haematobium and S. mansoni were prevalent in the three communities, with the prevalence of S. haematobium ranging from 3.3% (24/679; 95% CI = 1.9-4.7) to 19% (114/632; 95% CI = 15.8-22.2) and S. mansoni ranging from 30% (202/679; 95% CI = 26.5-33.5) to 78.3% (409/536; 95% CI = 74.7-81.9). The total prevalence of STH across all three sites was negligible at 1.3% (24/1847; 95% CI = 0.8-1.9) comprising mainly hookworm (10/1847). Multivariable statistical models indicated males to be 2.3 (95% CI = 1.7-3.3) times more likely to have a high intensity S. mansoni infection and 1.5 (95% CI = 1.1-2) times more likely to have a high intensity of S. haematobium infection compared to females. There was no significant difference in the likelihood of infection with S. mansoni between adults and school age children (SAC), however S. haematobium infections were found to be 2.5 (95% CI = 1.8-3.5) times more likely to occur in school age children than in adults. Multivariable statistical models (adjusted for age and sex) indicated an association between schistosomiasis and a number of self-reported morbidity indicators (notably diarrhoea and blood in stool and urine). Low socio-economic status was also associated with SCH infection (OR: 2; 95% CI = 1.3-3.2).ConclusionThe communities targeted by this study showed a range of Schistosoma prevalence's of infection, from hypo-endemic through to meso-endemic and hyper-endemic. The prevalence of SCH across the different age groups in the study locations highlights the large number of individuals currently being left out of the standard morbidity control method of annual treatment of the SAC.

Phase Ib/II oncology trials, despite their small sample sizes, aim to provide information for optimal internal company decision‐making concerning novel drug development. Hybrid controls (a combination of the current control arm and controls from one or more sources of historical trial data [HTD]) can be used to increase statistical precision. Here we assess combining two sources of Roche HTD to construct a hybrid control in targeted therapy for decision‐making via an extensive simulation study. Our simulations are based on the real data of one of the experimental arms and the control arm of the MORPHEUS‐UC Phase Ib/II study and two Roche HTD for atezolizumab monotherapy. We consider potential complications such as model misspecification, unmeasured confounding, different sample sizes of current treatment groups, and heterogeneity among the three trials. We evaluate two frequentist methods (with both Cox and Weibull accelerated failure time [AFT] models) and three different commensurate priors in Bayesian dynamic borrowing (with a Weibull AFT model), and modifications within each of those, when estimating the effect of treatment on survival outcomes and measures of effect such as marginal hazard ratios. We assess the performance of these methods in different settings and the potential of generalizations to supplement decisions in early‐phase oncology trials. The results show that the proposed joint frequentist methods and noninformative priors within Bayesian dynamic borrowing with no adjustment on covariates are preferred, especially when treatment effects across the three trials are heterogeneous. For generalization of hybrid control methods in such settings, we recommend more simulation studies. [ABSTRACT FROM AUTHOR]

Latin American and the Caribbean countries exhibit high life expectancy and projections show that they will experience the fastest growth of older people in the following years. As people live longer, it is important to maximise the opportunity to age healthily. We aimed to examine the associations of lifestyle behaviours with healthy ageing in Cuba, Dominican Republic, Peru, Mexico and Puerto Rico, part of the 10/66 study. Residents 65 years old and over (n = 10,900) were interviewed between 2003 and 2010. In the baseline survey, we measured four healthy behaviours: Physical activity, non-smoking, moderate drinking and fruits or vegetables consumption. Healthy ageing was conceptualised within the functional ability framework over a median of 4 years follow-up. Logistic models were calculated per country and then pooled together with fixed-effects meta-analysis. People engaging in physical activity and consuming fruits or vegetables had increased odds of healthy ageing in the follow-up (OR: 2.59, 95% CI: 2.20⁻3.03; OR: 1.24, 95% CI: 1.06⁻1.44, respectively). Compared with participants engaging in none or one healthy behaviour, the ORs of participants engaging in two, three or four healthy behaviours increased in a linear way (OR: 1.60, 95% CI: 1.40⁻1.84; OR: 2.29, 95% CI: 1.94⁻2.69; OR: 2.46, 95% CI: 1.54⁻3.92, respectively). Our findings highlight the importance of awareness of a healthy lifestyle behaviour among older people.

OBJECTIVE: We aimed to assess the health impact of a national control programme targeting schistosomiasis and intestinal nematodes in Uganda, which has provided population-based anthelmintic chemotherapy since 2003. METHODS: We conducted longitudinal surveys on infection status, haemoglobin concentration and clinical morbidity in 1871 randomly selected schoolchildren from 37 schools in eight districts across Uganda at three time points - before chemotherapy and after one year and two years of annual mass chemotherapy. FINDINGS: Mass treatment with praziquantel and albendazole led to a significant decrease in the intensity of Schistosoma mansoni - 70% (95% confidence interval (CI): 66-73%) after one year and 82% (95% CI: 80-85%) after two years of treatment. Intensity of hookworm infection also decreased (75% and 93%; unadjusted). There was a significant increase in haemoglobin concentration after one (0.135 g/dL (95% CI: 0.126-0.144)) and two years (0.303 g/dL (95% CI: 0.293-0.312)) of treatment, and a significant decrease in signs of early clinical morbidity. The impact of intervention on S. mansoni prevalence and intensity was similar to that predicted by mathematical models of the impact of chemotherapy on human schistosomiasis. Improvements in haemoglobin concentration were greatest among children who were anaemic or harbouring heavy S. mansoni infection at baseline. CONCLUSION: Anthelmintic treatment delivered as part of a national helminth control programme can decrease infection and morbidity among schoolchildren and improve haemoglobin concentration.

Objective To evaluate the impact on schistosomiasis of biennial treatment with praziquantel (PZQ) among school-age children in Burkina Faso, the first country that achieved full national coverage with treatment of more than 90% of the school-age population. Methods A cohort of 1727 schoolchildren (6-14 years old) was monitored at yearly intervals through a longitudinal survey. Additional groups of schoolchildren were monitored in cross-sectional surveys. Parasitological examinations for Schistosoma haematobium and Schistosoma mansoni were performed, and prevalence and intensity of infection before and after treatment were analysed. Findings Data from the longitudinal cohort show that a single round of PZQ treatment significantly reduced prevalence of S. haematobiurn infection by 87% (from 59.6% to 7.7%) and intensity of infection by 92.8% (from 94.2 to 6.8 eggs/10 ml of urine) 2 years post-treatment. The impact on infection was also confirmed by a cross-sectional survey 2 years post-treatment. Importantly, the proportion of school-age children with heavy S. haematobium infection decreased from around 25% before treatment to around 2-3% 2 years post-treatment. Cross-sectional comparison of S. haematobium infection in 7-year-old children in their first year at school, who received treatment through community-based drug delivery, also showed significant reduction in both prevalence (65.9%) and intensity of S. haematobium infection (78.4%) 2 years after single treatment. A significant reduction in S. mansoni infection was also achieved. Conclusion Significant and sustained reduction in S. haematobium infection was achieved by biennial treatment in school-age children in Burkina Faso. This may provide a cost-effective treatment strategy for similar national schistosomiasis control programmes in sub-Saharan Africa. Objectif Evaluer l&apos;impact sur la schistosomiase du traitement biennal contre la schistosomiase par le praziquantel (PZQ) chez les enfants d&apos;age scolaire du Burkina Faso, premier pays ayant obtenu une couverture nationale totale par ce traitement de plus de 90 % de la population d&apos;age scolaire. Methodes Une cohorte de 1727 ecoliers (6-14 ans) a ete suivie a intervalles d&apos;un an, a travers une enquete longitudinale. D&apos;autres groupes d&apos;ecoliers ont ete suivis dans le cadre d&apos;enquetes transversales. Des examens parasitologiques, visant a mettre en evidence Schistosoma haematobium et Schistosoma mansoni, ont ete pratiques. La prevalence et l&apos;intensite de l&apos;infestation avant et apres le traiternent ont egalement ete analysees. Resultats Les donnees collectees pour la cohorte longitudinale montrent qu&apos;une tournee unique de traitement par le PZQ a permis de reduire la prevalence de l&apos;infestation par S. haematobium de 87 % (baisse considerable de 59,6 % a 7,7 %) et l&apos;intensite de cette infestation de 92,8 % (baisse de 94,2 a 6,8 oeufs/10 ml d&apos;urine) deux ans apres le traitement. Cet effet sur I&apos;infestation a ete confirme par une enquete transversale realisee 2 ans egalement apres le traitement. Point important : la proportion d&apos;enfants d&apos;age scolaire lourdement infestes par S. haematobium est tombee de pres de 25 % avant le traitement a environ 2-3 % deux ans apres celui-ci. Des comparaisons transversales chez les enfants de 7 ans en premiere annee d&apos;ecole primaire, ayant recu le traitement par le biais des systemes de delivrance communautaires, ont mis en evidence une diminution a la fois de la prevalence (65,9 %) et de l&apos;intensite (78,4 %) de I&apos;infestation par S. haematobium deux ans apres le traitement unique. Ces comparaisons relevaient aussi une baisse consequente de l&apos;infestation par S. mansoni. Conclusion Une diminution importante et durable de l&apos;infestation par S. haematobium a ete obtenue par un traitement biennal des enfants d&apos;age scolaire au Burkina Faso. Cette demarche pourrait constituer une strategie de traitement d&apos;un bon rapport cout/ efficacite pour d&apos;autres programmes nationaux analogues de lutte contre la schistosomiase en Afrique sub-saharienne. Objetivo Evaluar el impacto en la esquistosomiasis a los dos anos del tratamiento bienal con prazicuantel (PZQ) en una poblacion de ninos en edad escolar en Burkina Faso, el primer pais que logro la plena cobertura nacional tratando a mas del 90% de la poblacion en edad escolar. Metodos Se realizo un estudio longitudinal para seguir la evolucion de una cohorte de 1727 escolares (6-14 anos) a intervalos de un ano. Se sometio tambien a seguimiento a otros grupos de escolares mediante encuestas transversales. Se realizaron examenes parasitologicos para detectar la presencia de Schistosoma haematobium y Schistosoma mansoni, determinandose la prevalencia e intensidad de la infeccion antes y despues del tratamiento. Resultados Los datos de la cohorte longitudinal muestran que, transcurridos dos anos, una sola ronda de tratamiento con PZQ habia reducido considerablemente la prevalencia -un 87% (de 59,6% a 7,7%)- e intensidad -92,8% (de 94,2 a 6,8 huevos/10 ml de orina)- de la infeccion por S. haematobium. El impacto en la infeccion se vio confirmado tambien por una encuesta transversal realizada a los 2 anos del tratamiento. Un dato importante es que la proporcion de ninos en edad escolar con infeccion seria disminuyo de aproximadamente un 25% antes del tratamiento a un 2%-3% a los 2 anos del mismo. La comparacion transversal del estado de infeccion por S. haematobium entre ninos de 7 anos en su primer ano de escolaridad, que recibieron tratamiento gracias a un sistema de suministro de medicamentos basado en la comunidad, tambien puso de relieve una reduccion importante tanto de la prevalencia (65,9%) como de la intensidad (78,4%) de la infeccion por S. haematobium dos anos despues del tratamiento unico. Tambien se logro reducir de forma notable la infeccion por S. mansoni. Conclusion El tratamiento bienal de los ninos en edad escolar en Burkina Faso logro reducir considerablemente y de forma sostenida la infeccion por S. haematobium. Este brindaria una estrategia de tratamiento costoeficaz para otros programas nacionales similares de control de la esquistosomiasis en el Africa subsahariana., Introduction Two main forms of human schistosomiasis or bilharzia exist in Africa--urinary schistosomiasis caused by Schistosoma haematobium infection and intestinal schistosomiasis caused by Schistosoma mansoni infection. "There are around 165 [...]

Objective We aimed to assess the health impact of a national control programme targeting schistosomiasis and intestinal nematodes in Uganda, which has provided population-based anthelmintic chemotherapy since 2003. Methods We conducted longitudinal surveys on infection status, haemoglobin concentration and clinical morbidity in 1871 randomly selected schoolchildren from 37 schools in eight districts across Uganda at three time points--before chemotherapy and after one year and two years of annual mass chemotherapy. Findings Mass treatment with praziquantel and albendazole led to a significant decrease in the intensity of Schistosoma mansoni--70% (95% confidence interval (CI): 66-73%) after one year and 82% (95% CI: 80-85%) after two years of treatment. Intensity of hookworm infection also decreased (75% and 93%; unadjusted). There was a significant increase in haemoglobin concentration after one (0.135 g/dL (95% CI: 0.126-0.144)) and two years (0.303 g/dL (95% Cl: 0.293-0.312)) of treatment, and a significant decrease in signs of early clinical morbidity. The impact of intervention on S. mansoni prevalence and intensity was similar to that predicted by mathematical models of the impact of chemotherapy on human schistosomiasis. Improvements in haemoglobin concentration were greatest among children who were anaemic or harbouring heavy 5. mansoni infection at baseline. Conclusion Anthelmintic treatment delivered as part of a national helminth control programme can decrease infection and morbidity among schoolchildren and improve haemoglobin concentration. Bulletin of the World Health Organization 2007;85:91-99. Resume Objectif Nous nous sommes efforces d&apos;evaluer l&apos;impact sur la sante d&apos;un programme national de lutte contre la schistosomiase et contre les nematodes intestinaux en Ouganda, qui dispense une chimiotherapie antihelminthique en population depuis 2003. Methodes Nous avons realise une enquete Iongitudinale sur le statut infectieux, le taux d&apos;hemoglobine et la morbidite clinique chez 1871 ecoliers, choisis au hasard parmi 37 ecoles relevant de 8 districts, repartis a travers l&apos;Ouganda, en mesurant ces parametres a trois moments differents : avant chimiotherapie, un an apres une chimiotherapie massive annuelle et deux ans apres ce traitement. Resultats Le traitement massif par le praziquantel et l&apos;albendazole a entraine une diminution importante de l&apos;intensite de l&apos;infestation par Schistosoma Mansoni: 70 % [intervalle de confiance a 95 % (IC) = 66 - 73 %] apres un an et 82 % [intervalle de confiance 95 % (IC) = 80 - 85 %] apres deux ans de traitement. L&apos;intensite de l&apos;infestation par les ankylostomes a aussi baisse [de 75 % et de 93 % respectivement (valeurs non ajustees)]. On a releve une hausse importante du taux d&apos;hemoglobine apres un an [0,135 g/dl (IC a 95 % = 0,126 - 0,144)] et deux ans [0,303 g/dl (IC a 95 % = 0,293 - 0,312)] de traitement et une diminution notable des signes precoces de morbidite clinique. L&apos;impact de l&apos;intervention sur les concentrations de 5. mansoni a ete similaire celui prevu par des modules de l&apos;impact de la chimiotherapie sur la schistosomiase humaine. C&apos;est chez les enfants anemiques ou fortement infestes par S. mansoniau depart que l&apos;on a releve les plus fortes ameliorations du taux d&apos;hemoglobine. Conclusion Le traitement antihelminthique delivre dans le cadre d&apos;un programme national de lutte contre les helminthes est en mesure de faire baisser les taux d&apos;infestation et de morbidite chez les ecoliers et d&apos;ameliorer leur taux d&apos;hemoglobine. Resumen Objetivo Decidimos evaluar el impacto sanitario de un programa nacional de control centrado en la esquistosomiasis y las infecciones intestinales por nematodos en Uganda, pais que viene proporcionando tratamiento antihelmintico a nivel poblacional desde 2003. Metodos Realizamos estudios longitudinales sobre la intensidad de la infeccion, la concentracion de hemoglobina y la morbilidad clinica en 1871 escolares seleccionados al azar en 37 escuelas de ocho distritos de Uganda en tres momentos: antes del tratamiento, y al cabo de uno y dos anos de la antibioticoterapia masiva anual. Resultados El tratamiento masivo con prazicuantel y albendazol se tradujo en una importante disminucion de la intensidad de la infeccion por Schistosoma mansoni: 70% (intervalo de confianza (IC) del 95%: 66%-73%) al cabo de un ano, y 82% (IC95%: 80%-85%) a los dos anos de tratamiento. La intensidad de la anquilostomiasis tambien disminuyo (75% y 93%; cifras no ajustadas). Se produjo un aumento considerable de la concentracion de hemoglobina al cabo de un ano (0,135 g/dl (IC95%: 0, 126-0, 144)) y a los dos anos (0,303 g/dl (IC95%: 0,293-0,312)) de tratamiento, asi como una disminucion significativa de los signos de morbilidad clinica precoz. El impacto de la intervencion en la prevalencia y la intensidad de la infeccion por S. mansoni fue similar al proyectado por los modelos matematicos del impacto de la antibioticoterapia en la esquistosomiasis humana. La concentracion de hemoglobina mejoro sobre todo entre los ninos que estaban anemicos o que presentaban signos serios de infeccion por S. mansoni al comienzo del estudio. Conclusion El tratamiento antihelmintico suministrado en el marco de un programa nacional de control de helmintos permite reducir la intensidad de la infeccion y la morbilidad entre los escolares y mejorar la concentracion de hemoglobina., Une traduction en francais de ce resume figure a la fin d l'article. Al final del articulo se facilita una traduccion al espanol. Introduction In Africa, schistosomiasis occurs predominantly due [...]

BackgroundSince the start of the 2009 influenza A pandemic (H1N1pdm), the World Health Organization and its member states have gathered information to characterize the clinical severity of H1N1pdm infection and to assist policy makers to determine risk groups for targeted control measures.Methods and findingsData were collected on approximately 70,000 laboratory-confirmed hospitalized H1N1pdm patients, 9,700 patients admitted to intensive care units (ICUs), and 2,500 deaths reported between 1 April 2009 and 1 January 2010 from 19 countries or administrative regions--Argentina, Australia, Canada, Chile, China, France, Germany, Hong Kong SAR, Japan, Madagascar, Mexico, The Netherlands, New Zealand, Singapore, South Africa, Spain, Thailand, the United States, and the United Kingdom--to characterize and compare the distribution of risk factors among H1N1pdm patients at three levels of severity: hospitalizations, ICU admissions, and deaths. The median age of patients increased with severity of disease. The highest per capita risk of hospitalization was among patients ConclusionsOur results demonstrate that risk factors for severe H1N1pdm infection are similar to those for seasonal influenza, with some notable differences, such as younger age groups and obesity, and reinforce the need to identify and protect groups at highest risk of severe outcomes. Please see later in the article for the Editors' Summary.

BACKGROUND: Intestinal schistosomiasis and soil-transmitted helminth (STH) infections constitute major public health problems in many parts of sub-Saharan Africa. In this study we examined the functional significance of such polyparasite infections in anemia and undernutrition in Rwandan individuals. METHODS: Three polyparasite infection profiles were defined, in addition to a reference profile that consisted of either no infections or low-intensity infection with only one of the focal parasite species. Logistic regression models were applied to data of 1,605 individuals from 6 schools in 2 districts of the Northern Province before chemotherapeutic treatment in order to correctly identify individuals who were at higher odds of being anaemic and/or undernourished. FINDINGS: Stunted relative to nonstunted, and males compared to females, were found to be at higher odds of being anaemic independently of polyparasite infection profile. The odds of being wasted were 2-fold greater for children with concurrent infection of at least 2 parasites at M+ intensity compared to those children with the reference profile. Males compared to females and anaemic compared to nonanaemic children were significantly more likely to be stunted. None of the three polyparasite infection profiles were found to have significant effects on stunting. CONCLUSION: The present data suggest that the levels of polyparasitism, and infection intensities in the Rwandan individuals examined here may be lower as compared to other recent similar epidemiological studies in different regions across sub-Saharan Africa. Neither the odds of anaemia nor the odds of stunting were found to be significantly different in the three-polyparasite infection profiles. However, the odds of wasting were higher in those children with at least two parasites at M+ intensity compared to those children with the reference profile. Nevertheless, despite the low morbidity levels indicated in the population under study here, we recommend sustainable efforts for the deworming of affected populations to be continued in order to support the economic development of the country.