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Background: It has been hypothesized that schistosomiasis negatively influences immune reconstitution in people living with HIV starting antiretroviral therapy (ART). In this study, we investigated the effect of schistosomiasis on the course of HIV infection in patients starting ART in a rural part of Tanzania., Methodology: Retrospective study including patients prospectively enrolled in a HIV cohort in Ifakara, south-central Tanzania between January 1, 2013 and April 1, 2015. Schistosomal circulating anodic antigen (CAA) was assessed in pre-ART cryopreserved plasma. Regression models were utilized to estimate the effect of CAA positivity on virological and immunological failure and a composite outcome of death/loss to follow-up (LFU)., Principal Findings: At ART-initiation 19.1% (88/461) of patients were CAA-positive. A tendency of higher CD4 increases was seen in CAA-positive patients (+182 cells/μl, interquartile range (IQR), 87-285 cells/μl) compared to CAA-negative patients (+147 cells/μl, IQR, 55-234 cells/μl, p = 0.09) after 10 months of follow-up. After adjustment for baseline risk factors, CAA-positivity showed no association with virological or immunological failure. In CAA-positive patients, 22.7% (20/88) died or were LFU, compared to 29.5% (110/373) of CAA-negative patients (hazard ratio (HR): 0.76, 95% confidence interval (CI), 0.47-1.22, p = 0.25). After adjustment for age, sex, body mass index, educational attainment, WHO-stage, tuberculosis status, and year of ART initiation, CAA-positivity showed a trend of a decreased hazard of death/LFU (HR: 0.58, 95% CI: 0.32-1.05, p = 0.07), while CD4 count at baseline (HR: 0.86, 95% CI: 0.76-1.00, p = 0.02) and MXD (sum of eosinophils, basophils, and monocytes counts) >1,100 cells/μl (HR: 0.56, 95% CI: 0.34-0.93, p = 0.03) were identified as independently protective factors., Conclusions/significance: Schistosomiasis is prevalent in this HIV cohort and may be beneficial for immunological reconstitution, while no effect on virological failure was apparent. A positive effect of schistosomiasis-induced immunomodulation on survival and retention in care needs confirmation in future studies., Competing Interests: The authors have declared that no competing interests exist.

Background: After decades of praziquantel mass drug administration (MDA), several countries approach schistosomiasis elimination. Continuing MDA in largely uninfected populations no longer seems justified. Alternative interventions to maintain the gains or accelerate interruption of transmission are needed. We report results, strengths, and shortcomings of novel test-treat-track-test-treat (5T) interventions in low Schistosoma haematobium prevalence areas on Pemba, Tanzania. Methods: School- and household-based surveys were conducted in 2021 and 2022 to monitor the S. haematobium and microhematuria prevalence and assess the impact of interventions. In 2021, 5T interventions were implemented in 15 low-prevalence areas and included: (i) testing schoolchildren in primary and Islamic schools for microhematuria as a proxy for S. haematobium, (ii) treating positive children, (iii) tracking them to their households and to water bodies they frequented, (iv) testing individuals at households and water bodies, and (v) treating positive individuals. Additionally, test-and-treat interventions were implemented in the 22 health facilities of the study area. Results: The S. haematobium prevalence in the school-based survey in 15 low-prevalence implementation units was 0.5% (7/1560) in 2021 and 0.4% (6/1645) in 2022. In the household-based survey, 0.5% (14/2975) and 0.7% (19/2920) of participants were infected with S. haematobium in 2021 and 2022, respectively. The microhematuria prevalence, excluding trace results, in the school-based survey was 1.4% (21/1560) in 2021 and 1.5% (24/1645) in 2022. In the household-based survey, it was 3.3% (98/2975) in 2021 and 5.4% (159/2920) in 2022. During the 5T interventions, the microhaematuria prevalence was 3.8% (140/3700) and 5.8% (34/594) in children in primary and Islamic schools, respectively, 17.1% (44/258) in household members, and 16.7% (10/60) in people at water bodies. In health facilities, 19.8% (70/354) of patients tested microhematuria-positive. Conclusions: The targeted 5T interventions maintained the very low S. haematobium prevalence and proved straightforward and feasible to identify and treat many of the few S. haematobium-infected individuals. Future research will show whether 5T interventions can maintain gains in the longer-term and expedite elimination. Trial registration: ISRCTN, ISCRCTN91431493. Registered 11 February 2020, https://www.isrctn.com/ISRCTN91431493. [ABSTRACT FROM AUTHOR]

Background: Schistosomiasis elimination has gained renewed priority in the WHO guidance documents published in 2020 and 2022. The SchistoBreak project, implemented in Pemba, Tanzania between 2020 and 2024, aims to assess new tools and strategies for shifting from elimination as a public health problem towards interruption of transmission. Here we report our baseline findings and discuss implications for future interventions. Methods: In 2020, human water contact sites (HWCSs) in the study area were geolocated and snail surveys were conducted. A parasitological and questionnaire cross-sectional baseline survey was implemented in 20 communities and their 16 primary schools between November 2020 and February 2021. Urine samples were collected at the school and household levels from individuals aged ≥ 4 years. Schistosoma haematobium infection was detected by urine filtration microscopy. Snail, parasitological and questionnaire-derived data were analyzed descriptively, spatially and with generalized estimated equation models. Results: The intermediate host snail Bulinus globosus was detected in 19.8% (33/167) of HWCSs. The overall S. haematobium prevalence was 1.2% (26/2196) in school-aged children and 0.8% (31/3893) in community members, with 0.2% (4/2196) and 0.1% (3/3893) heavy-intensity infections, respectively. Children who studied < 1 km away from HWCSs with B. globosus had significantly higher odds for a S. haematobium infection than those attending a school located > 2 km away (odds ratio [OR]: 5.0; 95% confidence interval [CI]: 2.3–11.1). Individuals living in a house located < 1 km away from HWCSs with B. globosus had higher odds than those residing in > 2 km distance (OR: 18.0; 95% CI: 2.9–111.0). Self-reported praziquantel treatment coverage was 83.2% (2015/2423) in schoolchildren in the mass drug administration (MDA) conducted in August 2020. Coverage among adult community members was 59.9% (574/958), but only 34.8% (333/958) took praziquantel correctly. Conclusions: While the S. haematobium prevalence is very low in Pemba, there are many HWCSs with B. globosus situated close to schools or houses that pose a considerable risk of recrudescence. To maintain and accelerate the progress towards interruption of transmission, targeted and cost-effective interventions that are accepted by the community are needed; for example, snail control plus focal MDA, or test-and-treat in schools and households near infested waterbodies. [ABSTRACT FROM AUTHOR]

Background: Reagent strip to detect microhematuria as a proxy for Schistosoma haematobium infections has been considered an alternative to urine filtration for individual diagnosis and community-based estimates of treatment needs for preventive chemotherapy. However, the diagnostic accuracy of reagent strip needs further investigation, particularly at low infection intensity levels. Methods: We used existing data from a study conducted in Tanzania that employed urine filtration and reagent strip testing for S. haematobium in two villages, including a baseline and six follow-up surveys after praziquantel treatment representing a wide range of infection prevalence. We developed a Bayesian model linking individual S. haematobium egg count data based on urine filtration to reagent strip binary test results available on multiple days and estimated the relation between infection intensity and sensitivity of reagent strip. Furthermore, we simulated data from 3,000 hypothetical populations with varying mean infection intensity to infer on the relation between prevalence observed by urine filtration and the interpretation of reagent strip readings. Principal findings: Reagent strip showed excellent sensitivity even for single measurement reaching 100% at around 15 eggs of S. haematobium per 10 ml of urine when traces on reagent strip were considered positive. The corresponding specificity was 97%. When traces were considered negative, the diagnostic accuracy of the reagent strip was equivalent to urine filtration data obtained on a single day. A 10% and 50% urine filtration prevalence based on a single day sampling corresponds to 11.2% and 48.6% prevalence by reagent strip, respectively, when traces were considered negative, and 17.6% and 57.7%, respectively, when traces were considered positive. Conclusions/Significance: Trace results should be included in reagent strip readings when high sensitivity is required, but excluded when high specificity is needed. The observed prevalence of reagent strip results, when traces are considered negative, is a good proxy for prevalence estimates of S. haematobium infection by urine filtration on a single day. Author summary: Control of schistosomiasis, a parasitic worm infection affecting more than 200 million people worldwide, relies mainly on mass drug administration of praziquantel to school-age children as well as adults in areas where the disease is particularly rampant. The World Health Organization has set thresholds of observed prevalence that require intervention to reach the goal of eliminating schistosomiasis as a public health problem by 2025. Intervention thresholds are defined based on parasitologic methods, which is urine filtration for Schistosoma haematobium. There are alternative diagnostic methods to detect S. haematobium, such as the detection of blood in urine that is a common symptom of urogenital schistosomiasis. We determined the diagnostic sensitivity and specificity of a reagent strip to detect microhematuria using data from two villages in Tanzania at multiple time points (once before and several times after treatment with the deworming drug praziquantel) and translate the urine filtration intervention thresholds to reagent strip equivalents. We show that the reagent strip including trace results is almost perfectly sensitive for infections above 15 eggs of S. haematobium per 10 ml of urine and that a 10% observed prevalence by urine filtration corresponds to 17.6% observed prevalence by reagent strip including traces. [ABSTRACT FROM AUTHOR]

Background: Considerable progress towards the elimination of urogenital schistosomiasis was made by the Zanzibar Elimination of Schistosomiasis Transmission project from 2012 till 2016, when biannual praziquantel mass drug administration (MDA) alone or with additional snail control or behaviour change interventions were implemented. Annual MDA was continued in 2017 and 2018, but not in 2019, imposing a 16-month treatment gap. We monitored the Schistosoma haematobium prevalence from 2012 till 2020 and assessed recrudescence patterns with focus on 2020. Methodology: Repeated cross-sectional surveys were conducted from 2011/12 till 2020 in 90 communities and 90 schools in Zanzibar. Annually, around 4,500 adults and up to 20,000 schoolchildren were surveyed. The S. haematobium prevalence was detected by urine filtration and reagent strips. In 2020, risk factors for infection were investigated using generalized estimated equation models. Principal findings: In adults, the apparent S. haematobium prevalence was 3.9% in 2011 and 0.4% in 2020. In schoolchildren, the prevalence decreased from 6.6% in 2012 to 1.2% in 2019 with vicissitudes over the years. Prominent recrudescence of infection from 2.8% in 2019 to 9.1% (+225%) in 2020 was observed in 29 schools with historically moderate prevalences (≥10%). Compared with 2019, reinfection in 2020 was particularly striking in boys aged 9–16 years. Being male was a risk factor for infection in 2020 (adults: odds ratio (OR): 6.24, 95% confidence interval (95% CI): 1.96–19.60; schoolchildren: OR: 2.06, 95% CI: 1.52–2.78). Living near to a natural freshwater body significantly increased the odds of infection in adults (OR: 2.90, CI: 1.12–7.54). Conclusions/Significance: After 11 rounds of MDA over 7 years and a 16-month treatment gap, the urogenital schistosomiasis prevalence considerably rebounded in hotspot areas. Future elimination efforts in Zanzibar should focus on re-intensifying MDA plus additional interventions in hotspot areas. In low-prevalence areas, the strategy might be adapted from MDA to targeted surveillance-response. Author summary: Schistosomiasis is a neglected tropical disease caused by parasitic blood flukes of the genus Schistosoma. On the Zanzibar islands, United Republic of Tanzania, interventions to eliminate urogenital schistosomiasis commenced in 2012. From 2012 to 2016, the population was treated biannually with praziquantel and, additionally, some areas received mollusciciding against the intermediate host snail, or educational measures for behavior change. Mass drug administration (MDA) with praziquantel was continued annually in 2017 and 2018, but not in 2019. As a result of the interventions, the overall S. haematobium prevalence was reduced to 0.4% in adults and 3.4% in schoolchildren in 2020. However, in some areas, the MDA gap in 2019 resulted in a considerable rebound of infections. The recrudescence in 2020 was particularly striking for boys aged 9–16 years. In general, in 2020, male participants had higher odds of infection than females. Adults living near to a natural freshwater body also showed an increased risk of S. haematobium infection. Future elimination efforts in Zanzibar should focus on re-intensifying elimination interventions, including MDA, snail control and behavior change in hotspot areas. In low-prevalence areas, the strategy might be adapted from MDA to targeted interventions, such as surveillance-response. [ABSTRACT FROM AUTHOR]