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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.

Abstract Background Research has suggested the positive impact of physical activity on health and wellbeing in older age, yet few studies have investigated the associations between physical activity and heterogeneous trajectories of healthy ageing. We aimed to identify how physical activity can influence healthy ageing trajectories using a harmonised dataset of eight ageing cohorts across the world. Methods Based on a harmonised dataset of eight ageing cohorts in Australia, USA, Mexico, Japan, South Korea, and Europe, comprising 130,521 older adults (M age = 62.81, SD age = 10.06) followed-up up to 10 years (M follow-up = 5.47, SD follow-up = 3.22), we employed growth mixture modelling to identify latent classes of people with different trajectories of healthy ageing scores, which incorporated 41 items of health and functioning. Multinomial logistic regression modelling was used to investigate the associations between physical activity and different types of trajectories adjusting for sociodemographic characteristics and other lifestyle behaviours. Results Three latent classes of healthy ageing trajectories were identified: two with stable trajectories with high (71.4%) or low (25.2%) starting points and one with a high starting point but a fast decline over time (3.4%). Engagement in any level of physical activity was associated with decreased odds of being in the low stable (OR: 0.18; 95% CI: 0.17, 0.19) and fast decline trajectories groups (OR: 0.44; 95% CI: 0.39, 0.50) compared to the high stable trajectory group. These results were replicated with alternative physical activity operationalisations, as well as in sensitivity analyses using reduced samples. Conclusions Our findings suggest a positive impact of physical activity on healthy ageing, attenuating declines in health and functioning. Physical activity promotion should be a key focus of healthy ageing policies to prevent disability and fast deterioration in health.

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.

Neonatal invasive disease caused by Group B Streptococcus (GBS) is responsible for much acute mortality and long-term morbidity. To guide development of better prevention strategies, including maternal vaccines that protect neonates against GBS, it is necessary to estimate the burden of this condition globally and in different regions. Here, we present a Bayesian model that estimates country-specific invasive GBS (iGBS) disease incidence in children aged 0 to 6 days. The model combines different types of epidemiological data, each of which has its own limitations: GBS colonization prevalence in pregnant women, risk of iGBS disease in children born to GBS-colonized mothers and direct estimates of iGBS disease incidence where available. In our analysis, we present country-specific maternal GBS colonization prevalence after adjustment for GBS detection assay used in epidemiological studies. We then integrate these results with other epidemiological data and estimate country-level incidence of iGBS disease including in countries with no studies that directly estimate incidence. We are able to simultaneously estimate two key epidemiological quantities: the country-specific incidence of early-onset iGBS disease, and the risk of iGBS disease in babies born to GBS-colonized women. Overall, we believe our method will contribute to a more comprehensive quantification of the global burden of this disease, inform cost-effectiveness assessments of potential maternal GBS vaccines and identify key areas where data are necessary.

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]

For epidemiological work with soil transmitted helminths the recommended diagnostic approaches are to examine fecal samples for microscopic evidence of the parasite. In addition to several logistical and processing issues, traditional diagnostic approaches have been shown to lack the sensitivity required to reliably identify patients harboring low-level infections such as those associated with effective mass drug intervention programs. In this context, there is a need to rethink the approaches used for helminth diagnostics. Serological methods are now in use, however these tests are indirect and depend on individual immune responses, exposure patterns and the nature of the antigen. However, it has been demonstrated that cell-free DNA from pathogens and cancers can be readily detected in patient's urine which can be collected in the field, filtered in situ and processed later for analysis. In the work presented here, we employ three diagnostic procedures-stool examination, serology (NIE-ELISA) and PCR-based amplification of parasite transrenal DNA from urine-to determine their relative utility in the diagnosis of S. stercoralis infections from 359 field samples from an endemic area of Argentina. Bayesian Latent Class analysis was used to assess the relative performance of the three diagnostic procedures. The results underscore the low sensitivity of stool examination and support the idea that the use of serology combined with parasite transrenal DNA detection may be a useful strategy for sensitive and specific detection of low-level strongyloidiasis.

Urine microscopy is the standard diagnostic method for urogenital S. haematobium infection. However, this may lead to under-diagnosis of urogenital schistosomiasis, as the disease may present itself with genital symptoms in the absence of ova in the urine. Currently there is no single reliable and affordable diagnostic method to diagnose the full spectrum of urogenital S. haematobium infection. In this study we explore the classic indicators in the diagnosis of urogenital S. haematobium infection, with focus on young women.In a cross-sectional study of 1237 sexually active young women in rural South Africa, we assessed four diagnostic indicators of urogenital S. haematobium infection: microscopy of urine, polymerase chain reaction (PCR) of cervicovaginal lavage (CVL), urogenital symptoms, and sandy patches detected clinically in combination with computerised image analysis of photocolposcopic images. We estimated the accuracy of these diagnostic indicators through the following analyses: 1) cross tabulation (assumed empirical gold standard) of the tests against the combined findings of sandy patches and/or computerized image analysis and 2) a latent class model of the four indicators without assuming any gold standard.The empirical approach showed that urine microscopy had a sensitivity of 34.7% and specificity of 75.2% while the latent class analysis approach (LCA) suggested a sensitivity of 81.0% and specificity of 85.6%. The empirical approach and LCA showed that Schistosoma PCR in CVL had low sensitivity (14.1% and 52.4%, respectively) and high specificity (93.0% and 98.0, respectively). Using LCA, the presence of sandy patches showed a sensitivity of 81.6 and specificity of 42.4%. The empirical approach and LCA showed that urogenital symptoms had a high sensitivity (89.4% and 100.0%, respectively), whereas specificity was low (10.6% and 12.3%, respectively).All the diagnostic indicators used in the study had limited accuracy. Using urine microscopy or Schistosoma PCR in CVL would only confirm a fraction of the sandy patches found by colposcopic examination.

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.

BACKGROUND:Elimination of schistosomiasis as a public health problem and interruption of transmission in selected areas are key goals of the World Health Organization for 2025. Conventional parasitological methods are insensitive for the detection of light-intensity infections. Techniques with high sensitivity and specificity are required for an accurate diagnosis in low-transmission settings and verification of elimination. We determined the accuracy of a urine-based up-converting phosphor-lateral flow circulating anodic antigen (UCP-LF CAA) assay for Schistosoma haematobium diagnosis in low-prevalence settings in Zanzibar, Tanzania. METHODOLOGY:A total of 1,740 urine samples were collected in 2013 from children on Pemba Island, from schools where the S. haematobium prevalence was

(1) Background: Current international policy for schistosomiasis and soil-transmitted helminthiasis (STH) control emphasises mass administration of deworming drugs in school-based programmes. However, this approach is insufficient to control the transmission of these diseases, and their burden in non-school cohorts is recognised, albeit under-researched. This research will investigate the feasibility and acceptability of expanding access to praziquantel (PZQ) against schistosomiasis, and albendazole (ALB) against STH, to communities in selected transmission settings in Ghana. (2) Methods: A three-site longitudinal study will be implemented to investigate the effectiveness of expanding treatment strategies for PZQ and ALB to community members. In the context of community mass drug administration (to preschool children, school non-attending children, and adults, including pregnant women), the intervention will be assessed in a random sample of community members, at baseline with follow-up at 6, 12, and 18 months. In each community, 658 participants will be enrolled, and 314 followed up at each time point. The primary outcome measure is the prevalence of infection of Schistosoma haematobium and/or S. mansoni at study endpoint, as assessed by longitudinal surveys. Secondary outcomes are to quantify the infection of schistosomiasis and STH infections in non-treated cohorts, reductions in prevalence of STH, and intensity of schistosomiasis and STH, and treatment coverage. Nested within this study will be qualitative, cost-benefit, and cost-effectiveness evaluations that will explore accessibility, feasibility, and economic impact of expanded treatment from different complementary perspectives. (3) Discussion: Using a multidisciplinary approach, this study will generate evidence for improved availability, acceptability, affordability, and accessibility to deworming drugs against schistosomiasis and STH to individuals and communities in Ghana. This is likely to have considerable research, programmatic, and political value to contribute evidence for national programme policy development within Ghana, and, more broadly, World Health Organization policy development.

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'impact sur la schistosomiase du traitement biennal contre la schistosomiase par le praziquantel (PZQ) chez les enfants d'age scolaire du Burkina Faso, premier pays ayant obtenu une couverture nationale totale par ce traitement de plus de 90 % de la population d'age scolaire. Methodes Une cohorte de 1727 ecoliers (6-14 ans) a ete suivie a intervalles d'un an, a travers une enquete longitudinale. D'autres groupes d'ecoliers ont ete suivis dans le cadre d'enquetes transversales. Des examens parasitologiques, visant a mettre en evidence Schistosoma haematobium et Schistosoma mansoni, ont ete pratiques. La prevalence et l'intensite de l'infestation avant et apres le traiternent ont egalement ete analysees. Resultats Les donnees collectees pour la cohorte longitudinale montrent qu'une tournee unique de traitement par le PZQ a permis de reduire la prevalence de l'infestation par S. haematobium de 87 % (baisse considerable de 59,6 % a 7,7 %) et l'intensite de cette infestation de 92,8 % (baisse de 94,2 a 6,8 oeufs/10 ml d'urine) deux ans apres le traitement. Cet effet sur I'infestation a ete confirme par une enquete transversale realisee 2 ans egalement apres le traitement. Point important : la proportion d'enfants d'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'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'intensite (78,4 %) de I'infestation par S. haematobium deux ans apres le traitement unique. Ces comparaisons relevaient aussi une baisse consequente de l'infestation par S. mansoni. Conclusion Une diminution importante et durable de l'infestation par S. haematobium a ete obtenue par un traitement biennal des enfants d'age scolaire au Burkina Faso. Cette demarche pourrait constituer une strategie de traitement d'un bon rapport cout/ efficacite pour d'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 [...]

BACKGROUND:Diagnosis of urogenital schistosomiasis in chronically infected adults is challenging but important, especially because long term infection of the bladder and urinary tract can have dire consequences. We evaluated three tests for viable infection: detection of parasite specific DNA Dra1 fragments, haematuria and presence of parasite eggs for sensitivity (Se) and specificity (Sp). METHODS:Over 400 urine specimens collected from adult volunteers in an endemic area in Western Nigeria were assessed for haematuria then filtered in the field, the filter papers dried and later examined for eggs and DNA. The results were stratified according to sex and age and subjected to Latent Class analysis. CONCLUSIONS:Presence of Dra1 in males (Se=100%; Sp=100%) exceeded haematuria (Se=87.6%: Sp=34.7%) and detection of eggs (Se=70.1%; Sp=100%). In females presence of Dra1 was Se=100%: Sp=100%, exceeding haematuria (Se=86.7%: Sp=77.0%) and eggs (Se=70.1%; Sp=100%). Dra1 became undetectable 2 weeks after praziquantel treatment. We conclude detection of Dra1 fragment is a definitive test for the presence of Schistosoma haematobium infection.

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'evaluer l'impact sur la sante d'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'hemoglobine et la morbidite clinique chez 1871 ecoliers, choisis au hasard parmi 37 ecoles relevant de 8 districts, repartis a travers l'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'albendazole a entraine une diminution importante de l'intensite de l'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'intensite de l'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'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'impact de l'intervention sur les concentrations de 5. mansoni a ete similaire celui prevu par des modules de l'impact de la chimiotherapie sur la schistosomiase humaine. C'est chez les enfants anemiques ou fortement infestes par S. mansoniau depart que l'on a releve les plus fortes ameliorations du taux d'hemoglobine. Conclusion Le traitement antihelminthique delivre dans le cadre d'un programme national de lutte contre les helminthes est en mesure de faire baisser les taux d'infestation et de morbidite chez les ecoliers et d'ameliorer leur taux d'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.