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The World Health Organization calls for schistosomiasis endemic countries to regularly monitor the efficacy of Praziquantel (PZQ) drug, the only antischistosomal drug used for four decades in Tanzania. In response to that call, the current study investigated the efficacy of single dose of PZQ against Schistosoma haematobium during the high transmission season and further assessed, the sensitivity and specificity of urine reagent strips before and after treatment. The study recruited a total of 2,498 -children aged (4 -17 years old) who provided a single urine sample that was visually examined for macro-haematuria, then using urine dipstick and urine filtration technique for microhaematuria and the presence of S. haematobium eggs. The baseline prevalence of S. haematobium eggs positive based on urine filtration test was 29.2 % (95 %CI:27.5-31.0) and that of microhaematuria was 43.1 % (95 %CI:41.1-45.0). Of the infected participants, 40.9 % (95 %CI:37.4-44.6) had a heavy intensity of infection and the geometrical mean intensity (GMI) of infection was 33.7 eggs/10mls of urine. A single dose of PZQ reduced the prevalence of infection to 16.2 %, the GMI of infection to 18.8eggs/10mls of urine and that of microhaematuria to 27.9 %. Cure rate and egg reduction rates (ERR) were 83.8 % and 44.3 % respectively. At baseline, the sensitivity and specificity of the urine reagent strips were 59.7 % and 93.8 %, whereas at post-treatment they were 16.7 % and 93.6 %. When PZQ drug is administered during the high transmission season, its efficacy in term of ERR is poor. The urine reagent strips had low sensitivity but high specificity at pre-and-post PZQ treatment., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Humphrey Deogratias Mazigo reports financial support, administrative support, and statistical analysis were provided by National Institute for Health Research. Humphrey Mazigo reports a relationship with Catholic University of Health and Allied Sciences that includes: employment. None has patent pending to None. None If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Urogenital schistosomiasis remains as a public health problem in Tanzania and for the past 15 years, mass drug administration (MDA) targeting primary school children has remained as the mainstay for its control. However, after multiple rounds of MDA in highly risk groups, there are no data on the current status of Schistosoma haematobium in known endemic areas. Furthermore, the performance of commonly used diagnostic test, the urine reagent strips is not known after the decline in prevalence and intensities of infection following repeated rounds of treatment. Thus, after 15 of national MDA, there is a need to review the strategy and infection diagnostic tools available to inform the next stage of schistosomiasis control in the country., Methods/findings: A analytical cross-sectional study was conducted between October and November, 2019 among pre-school (3-5years old) and school aged children (6-17 years old) living in four (4) districts with low (<10%) and moderate (10%-<50%) endemicity for schistosomiasis as per WHO classification at the start of the national control programme in 2005/06, with mean prevalence of 20.7%. A total of 20,389 children from 88 randomly selected primary schools participated in the study. A questionnaire was used to record demographic information. A single urine sample was obtained from each participant and visually examined for macrohaematuria, tested with a dipstick for micro-haematuria, to determine blood in urine; a marker of schistosome related morbidity and a proxy of infection. Infection intensity was determined by parasitological examination of the urine sample for S. haematobium eggs. Overall, mean infection prevalence was 7.4% (95%CI: 7.0-7.7, 1514/20,389) and geometric mean infection intensity was 15.8eggs/10mls. Both infection prevalence (5.9% versus 9%, P<0.001) and intensity (t = -6.9256, P<0.001) were significantly higher in males compared to females respectively. Light and heavy infections were detected in 82.3% and 17.7% of the positive children respectively. The prevalence of macrohaematuria was 0.3% and that of microhaematuria was 9.3% (95%CI:8.9-9.7). The sensitivity and specificity of the urine reagent strip were 78% (95%CI: 76.1-79.9) and 99.8% (95%CI: 99.7-99.9). Having light (P<0.001) and heavy infection intensities (P<0.001) and living in the study districts increased the odd of having microhaematuria. Predictors of S. haematobium infection were being male (P<0.003), microhaematuria (P<0.001), and living in the three study districts (P<0.001) compared to living at Nzega district., Conclusion: The findings provide an updated geographical prevalence which gives an insight on the planning and implementation of MDA. Comparing with the earlier mapping survey at the start of the national wide mass drug administration, the prevalence of S. haematobium infection have significantly declined. This partly could be attributed to repeated rounds of mass drug administration. The urine reagent strips remain as a useful adjunct diagnostic test for rapid monitoring of urogenital schistosomiasis in areas with low and high prevalence. Based on prevalence levels and with some schools having no detectable infections, review of the current blanket mass drug administration is recommended., Competing Interests: The authors have declared that no competing interests exist.

As trachoma programs move towards eliminating trachoma as a public health problem, the number of surveys necessary to evaluate the status of trachomatous trichiasis (TT) increases. Currently, the World Health Organization endorses a district-level population-based prevalence survey for trachoma that involves a two-stage cluster design. We explored the validity of implementing this survey design in larger geographic areas to gain cost efficiencies. We evaluated the change in precision due to combining geographically contiguous and homogenous districts into single evaluation units (EUs) and modulating the sample size by running simulations on existing datasets. Preliminary findings from two opportunities in Tanzania show variability in the appropriateness in conducting this survey across larger geographies. These preliminary findings stress the importance of determining what is meant by homogeneity in terms of TT before combining multiple districts into a single EU.

Background: The World Health Organization (WHO) calls for schistosomiasis endemic countries to integrate schistosomiasis control measures into the primary health care (PHC) services; however, in Tanzania, little is known about the capacity of the primary health care system to assume this role. The objective of this study was to assess the capacity of the primary health care system to diagnose and treat schistosomiasis in endemic regions of north-western Tanzania., Methods: A total of 80 randomly-selected primary health care facilities located in the Uyui, Geita and Ukerewe districts of North-western Tanzania participated in the study. At each facility, the in-charge clinician, or any other healthcare worker appointed by the in-charge clinician, participated in the questionnaire survey. A quantitative questionnaire installed in a Data Tool Kit software was used to collect data. Healthcare workers working at various stations (laboratory, pharmacy, data clerks, outpatient section) were interviewed. The questionnaire collected information related to healthcare workers' knowledge about urogenital and intestinal schistosomiasis symptoms, human and material resources, laboratory services, data capture, and anti-schistosomiasis treatment availability., Results: A total of 80 healthcare workers were interviewed. Bloody stool (78.3 %) and haematuria (98.7 %) were the most common symptoms of intestinal and urogenital schistosomiasis mentioned by healthcare workers. Knowledge on the chronic symptoms such as hepatosplenomegaly and hematemesis for intestinal schistosomiasis, and oliguria and dysuria for urogenital schistosomiasis, were inadequate. Laboratory services were only available in 33.8 % (27/80) of the health facilities and direct wet preparation was the most common diagnostic technique used for both urine and stool samples. All healthcare workers knew that praziquantel was the drug of choice for the treatment of schistosomiasis and the drug was available in 91.3 % (73/80) of the health facilities., Conclusions: The capacity of the primary health care facilities included in the current study is inadequate in terms of diagnosis, treatment, reporting and healthcare workers' knowledge of schistosomiasis. Thus, the integration of schistosomiasis control activities into the primary healthcare system requires these gaps to be addressed.

Planning and implementation of schistosomiasis control activities requires an understanding of the prevalence, intensity of infection and geographical distribution of the disease in different epidemiological settings. Although, Tanzania is known to be highly endemic to schistosomiasis, there is paucity of data on the geographical distribution of schistosomiasis in potential large water bodies in the country. Thus, the present study was conducted to determine the prevalence, infection intensities and geographical distribution of schistosomiasis along villages located on the shoreline of Lake Nyasa, southern Tanzania. A cross-sectional study was conducted among 1560 children aged 1-13 years old living in villages located along the shoreline of Lake Nyasa. A single urine and stool sample was obtained from each participating child and screened for S. mansoni using Kato Katz (KK) technique to detect eggs and using point-of-care circulating Cathodic Antigen (POC-CCA) test to detect antigen in urine. Urine filtration technique was used to screen for S. haematobium eggs in urine samples. Villages/primary school were mapped using geographical information system and prevalence map was generated using ArcView GIS software. The overall prevalence of S. mansoni based on KK technique and POC-CCA test was 15.1% (95%CI: 13.4-16.9) and 21.8% (95%CI: 18.5-25.3) respectively. The prevalence S. haematobium was 0.83% (95%CI: 0.5-1.4) and that of haematuria was 0.9%. The arithmetic mean egg intensities for S. haematobium and S. mansoni were 18.5 mean eggs/10 ml (95%CI: 5.9-57.6) of urine and 34.7 mean epg (95%CI: 27.7-41.7) respectively. Villages located on the southern end of the lake had significantly high prevalence of S. mansoni than those located on the northern part (χ 2  = 178.7838, P = 0.001). Cases of S. haematobium were detected only in three villages. Both S. mansoni and S. haematobium infections occur in villages located along the shoreline of Lake Nyasa at varying prevalence. These finding provide insights that can provide guidance in planning and implementation of MDA approach and other recommended measures such as improvement in sanitation, provision of clean water and behaviour changes through public health education.

Trachoma programs use annual antibiotic mass drug administration (MDA) in evaluation units (EUs) that generally encompass 100,000-250,000 people. After one, three, or five MDA rounds, programs undertake impact surveys. Where impact survey prevalence of trachomatous inflammation-follicular (TF) in 1- to 9-year-olds is ≥ 5%, ≥ 1 additional MDA rounds are recommended before resurvey. Impact survey costs, and the proportion of impact surveys returning TF prevalence ≥ 5% (the failure rate or, less pejoratively, the MDA continuation rate), therefore influence the cost of eliminating trachoma. We modeled, for illustrative EU sizes, the financial cost of undertaking MDA with and without conducting impact surveys. As an example, we retrospectively assessed how conducting impact surveys affected costs in the United Republic of Tanzania for 2017-2018. For EUs containing 100,000 people, the median (interquartile range) cost of continuing MDA without doing impact surveys is USD 28,957 (17,581-36,197) per EU per year, whereas continuing MDA solely where indicated by impact survey results costs USD 17,564 (12,158-21,694). If the mean EU population is 100,000, then continuing MDA without impact surveys becomes advantageous in financial cost terms only when the continuation rate exceeds 71%. For the United Republic of Tanzania in 2017-2018, doing impact surveys saved enough money to provide MDA for > 1,000,000 people. Although trachoma impact surveys have a nontrivial cost, they generally save money, providing EUs have > 50,000 inhabitants, the continuation rate is not excessive, and they generate reliable data. If all EUs pass their impact surveys, then we have waited too long to do them.