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BackgroundMalaria continued to be the major public health concern in sub-Sahara Africa, thus for better planning of control activities, periodic surveillance of both clinical and asymptomatic cases remains important. However, the usability of routinely collected malaria data in Kenyan hospitals as a predictor of the asymptomatic malaria infection in the community amidst rapid infection resurgence or reduction in different areas of disease endemicities remains widely unstudied. This study was therefore aimed to evaluate the utility of passive surveillance of malaria in health facilities as a proxy of infection transmission of the surrounding community in different transmission intensities.MethodsProspective multiple cross-sectional surveys were done in three villages in western Kenya. Monthly asymptomatic malaria positivity among school children, number of outpatient (OPD) confirmed malaria cases and abundancy of indoor resting malaria vectors were surveyed from June 2015 to August 2016. Community surveys on antimalarial drug use among adults and children were also done. Detection of malaria parasitaemia was done using thick and thin Giemsa stained blood slide microscopy for both clinical and school participants. A questionnaire was used to collect information on self-use of antimalarial drugs from randomly selected households.ResultsThe overall OPD blood slide positivity from all study sites was 26.6% (95%CI 26.2-27.0) and highest being among the 5-14 years (41.2% (95% CI 40.1-42.3). Asymptomatic malaria positivity among the school children were 6.4% (95%CI 5.3-7.5) and 38.3% (95%CI 36.1-40.5) in low and high transmission settings respectively. A strong correlation between overall monthly OPD positivity and the school age children positivity was evident at Marani (low transmission) (rho = 0.78, p = 0.001) and at Iguhu (Moderate transmission) (rho = 0.61, p = 0.02). The high transmission setting (Kombewa) showed no significant correlation (rho = - 0.039, p = 0.89).ConclusionHospital malaria data from low and moderate malaria transmission predicted the infection transmission dynamics of the surrounding community. In endemic sites, hospital based passive surveillance didn't predict the asymptomatic infection dynamics in the respective community.

Background: Understanding the impact of intervention tools on vector behaviour, host preference, resting, and infectivity rates is paramount in malaria control planning. Magu district was one of the districts in lake zone regions in northwestern Tanzania covered with indoor residual spray and long-lasting insecticidal nets in the main malaria control campaign. After interventions, this study evaluated the mosquito's host preference and resting behaviour in Lugeye village in rainy and dry seasons. Methods: Mosquitoes were collected both indoors and outdoors using the rest pots. The collection was done in both rainy and dry seasons. The samples were collected bi-weekly for three months each season. Results: A total of 254 mosquitoes were collected in both dry and rainy seasons, indoors and outdoors. The most abundant species were Anopheles funestus s.s. and An.arabiensis. Most blood meals from bovines rested outdoors, while human blood meal sources rested outdoors. Sporozoite-positive mosquitoes were found only during the dry season. Conclusion: This study's findings have shown that implementing IRS and LLIN interventions has led to a species shift from An.gambiae s.s. to An.funestus and An.arabiensis. The inclusion of vector insecticide resistance information can be of paramount importance in appropriate intervention tool selection. [ABSTRACT FROM AUTHOR]

Background: Urogenital schistosomiasis caused by Schistosoma haematobium affects approximately 110 million people globally, with the majority of cases in low- and middle-income countries. Schistosome infections have been shown to impact the host immune system, gene expression, and microbiome composition. Studies have demonstrated variations in pathology between schistosome subspecies. In the case of S. haematobium, infection has been associated with HIV acquisition and bladder cancer. However, the underlying pathophysiology has been understudied compared to other schistosome species. This systematic review comprehensively investigates and assimilates the effects of S. haematobium infection on systemic and local host mucosal immunity, cellular gene expression and microbiome. Methods: We conducted a systematic review assessing the reported effects of S. haematobium infections and anthelmintic treatment on the immune system, gene expression and microbiome in humans and animal models. This review followed PRISMA guidelines and was registered prospectively in PROSPERO (CRD42022372607). Randomized clinical trials, cohort, cross-sectional, case-control, experimental ex vivo, and animal studies were included. Two reviewers performed screening independently. Results: We screened 3,177 studies and included 94. S. haematobium was reported to lead to: (i) a mixed immune response with a predominant type 2 immune phenotype, increased T and B regulatory cells, and select pro-inflammatory cytokines; (ii) distinct molecular alterations that would compromise epithelial integrity, such as increased metalloproteinase expression, and promote immunological changes and cellular transformation, specifically upregulation of genes p53 and Bcl-2; and (iii) microbiome dysbiosis in the urinary, intestinal, and genital tracts. Conclusion: S. haematobium induces distinct alterations in the host's immune system, molecular profile, and microbiome. This leads to a diverse range of inflammatory and anti-inflammatory responses and impaired integrity of the local mucosal epithelial barrier, elevating the risks of secondary infections. Further, S. haematobium promotes cellular transformation with oncogenic potential and disrupts the microbiome, further influencing the immune system and genetic makeup. Understanding the pathophysiology of these interactions can improve outcomes for the sequelae of this devastating parasitic infection. Author summary: The parasitic trematode S. haematobium affects 110 million people worldwide. Many studies have described the effects of schistosome infections on humans and animals, but data focusing solely on S. haematobium infections, which cause urogenital schistosomiasis are scarce. Our goal was to evaluate, in a systematic manner, how S. haematobium infection affects the immune system, gene expression and microbiome of the host. These effects are important because they could lead to increased risk of infections, such as HIV, and bladder cancer. We screened 3,179 studies for potential relevance and included 94 of them in this review. Our analysis showed that S. haematobium infection profoundly alters the immune system with a mixed pro-inflammatory and anti-inflammatory response, though with a predominant type 2 immune phenotype and increased regulatory cells. We further found consistent evidence that it impairs local mucosal epithelial barrier integrity, promotes cellular transformation with pro-oncogenic changes in the host, and is associated with microbial alterations in urine, stool, and genital tracts. We discuss how these findings might be interpreted, and the additional research needed, to improve our understanding of S. haematobium pathophysiology and ameliorate the potential sequelae of S. haematobium infection, such as increased viral infections and cancer. [ABSTRACT FROM AUTHOR]

Background: The diagnosis of Female Genital Schistosomiasis (FGS) which is a clinical feature of urogenital schistosomiasis caused by Schistosoma haematobium is challenging, especially in primary healthcare facilities characterized by low resources which are dependent by the majority of the FGS endemic communities. To facilitate and improve diagnosis in these settings, a simple risk factors and symptoms tool has been developed to help healthcare workers at primary healthcare facilities identify and manage FGS cases. However, the sensitivity and specificity of the tool are not known. Therefore, the objective of this study was to assess the performance of risk factors and symptoms tools in diagnosing FGS in adolescent girls and women of reproductive age in selected villages of north-western Tanzania. Methods: A community-based analytical cross-sectional study was conducted among 347 women aged 18–49 years in Maswa District, north-western Tanzania. A single urine sample was collected from each participant and screened for S. haematobium eggs using a urine filtration technique. Consenting participants (n = 177), underwent thorough speculum examination by trained gynaecologists using a digital portable colposcopy to capture images of the cervix and vagina. All the captured pictures were examined independently by two pairs (2 gynaecologists in each pair) of qualified obstetricians and gynaecologists. A descriptive analysis and logistic regression were used to demonstrate the prevalence, symptoms, and risk factors of FGS. Results: The mean age of 347 women enrolled in the study was 30 years (Standard Deviation (SD) ±7.7) and the prevalence of women with symptoms suggestive of FGS was 15.8% (95% CI; 10.8%- 22.0) by colposcope and 87% (95% CI; 83.0%-90.4%) using the risk factor and symptom checklist. The overall sensitivity, specificity, positive and negative predictive value of symptoms and risk factors checklist tool for diagnosing FGS schistosomiasis (≥7 score points) using colposcope as a reference test were 85.7% (95%CI; 80.6%- 90.9%), 8.7% (95%CI; 4.6%-12.9%), 15.0% (95%CI; 9.7%-20.3%) and 76.5% (95%CI; 70.2%-82.7%). Multivariate analysis showed that female genital schistosomiasis using a risk factor and symptom checklist was associated with fetching water in contaminated fresh water (aOR:21.8, 95%CI;2.8–171.2, P <0.003), self-reported pelvic pain (aOR:5.3, 95%CI; 1.1–25.9, P< 0.04) and having any urinary symptoms (aOR:12.2, 95%CI; 1.5–96.3, P<0.018). Urine microscopy results were available for 345 participants, of these, 3.5% (12/345) (95% CI; 1.8%-6.0%) were positive for S. haematobium infection. Conclusion: Female genital schistosomiasis and urinary-related symptoms are common in the current study population. The risk factor and symptoms checklist for diagnosis of FGS achieved high sensitivity but low specificity for women who scored ≥7 points using colposcope as a reference diagnostic test. At present, the call to integrate FGS into the reproductive health services for women has received much attention, however, the diagnostic part of FGS remains a challenge, thus there is a need to continue evaluating this tool in different population and age structures in endemic areas. Author summary: Female genital schistosomiasis (FGS) is a genital manifestation of a waterborne parasitic disease caused by Schistosoma haematobium, however, it is mostly neglected. FGS diagnosis is still a challenge due to the lack of reference standards for its diagnosis. Colposcope has been used as a standard for diagnosing FGS, it shows the FGS clinical findings on the cervix and vagina. However, FGS diagnosis by colposcope has not been feasible in most rural endemic settings due to its unavailability, low level of knowledge of its use for diagnosing FGS, and low FGS knowledge among healthcare workers. Thus, there is a need to develop an alternative cheap diagnostic tool to be used in endemic areas for identifying women and adolescent girls at high risk of having FGS lesions and referring them for colposcopy examination. This call has been given more weight by the WHO in its roadmap plan for ending Neglected Tropical Diseases (NTD) by 2030. In response to this call, this study determined the sensitivity and specificity of the risk factors and symptoms checklist (variables), and the prevalence of FGS by both colposcope and risk factors and symptoms checklist using a score point of 7 as a cut-off point to suspect FGS. Furthermore, we also determined the prevalence of S. haematobium infection using a urine filtration technique and determined the symptoms and risk factors of urogenital schistosomiasis among women in selected villages of Maswa district, north-western Tanzania. The findings of this study demonstrated a high prevalence of FGS in the current study population using both methods/diagnoses. There is a need for further evaluation of the performance of the risk and symptoms questionnaire to improve its performance. Furthermore, there is a need to integrate the FGS services into a wide spectrum of reproductive health services, to allow women with urogenital symptoms to receive treatment. [ABSTRACT FROM AUTHOR]

Soil-transmitted helminthiases (STH) are among the neglected tropical diseases and infect more than 24% of the world population. The World Health Organization recommends regular monitoring of STH's prevalence and intensity following mass drug administrations to evaluate their effectiveness and inform future control strategies. This study evaluated the prevalence, intensity, and risk factors of STH infections among school children aged 6 to 14 years old in northwestern Tanzania. A cross-sectional study was conducted among 728 school children in the Kagera region in 2021. Participants were selected using a two-stage cluster sampling method. A questionnaire was used to collect data on the risk factors. Stool samples were examined using the Kato–Katz technique. The data were analysed using STATA. The overall prevalence of STH was 56.2% (95% CI: 52.5–59.8, 409/728). About 5.7% and 1.1% of the infected children had moderate-intensity infections with Ascaris lumbricoides and Trichuris trichiura, respectively. Risk factors included the mother's occupation as a farmer (aOR: 1.2, p = 0.002) and not washing hands with water and soap (aOR: 1.4, p = 0.035). Washing one's hands after using the toilet (aOR: 0.6; p = 0.024) is a preventive measure against STH infections. STH was prevalent in the study area. The mother's occupation (farmer) and the lack of handwashing with water and soap influenced STH transmission. Conversely, washing hands after visiting the toilet and after playing with soil reduced the risk of STH infection. [ABSTRACT FROM AUTHOR]

Schistosoma haematobium, the parasite that causes urogenital schistosomiasis, is widely prevalent in Tanzania. In addition to well-known effects on the urinary tract, S. haematobium also causes clinically- evident damage to the reproductive tract in approximately half of infected women, which is known as female genital schistosomiasis (FGS). FGS has major gynecologic and social consequences on women's reproductive health, yet little information is available regarding FGS in Tanzania. To cover that gap, we conducted the present scoping review to examine the epidemiology of FGS in Tanzania (both in the mainland and Zanzibar island) and to make recommendations for future work in this area. The available evidence from community-based and hospital-based retrospective studies indicates that FGS is a significant health problem in the country. Very few community-based studies have been reported from mainland Tanzania, and Zanzibar. Our review highlights the scarcity of efforts to address FGS in Tanzania and the need for additional community-based studies. The studies will help us understand the true burden of the disease nationwide, to assess the impact of praziquantel on FGS lesions, and to address social and mental health in relation to FGS. This review emphasizes integration of delivery of FGS related services in primary health care systems through the reproductive health clinics which covers sexually transmitted infections, HIV and cervical cancer screening. These actions are essential if this neglected gynecological disease is to be addressed in Tanzania. Author summary: Female genital schistosomiasis (FGS) caused by Schistosoma haematobium affects mostly the reproductive tract of girls and women in rural and marginalized communities. This disease has been largely neglected by the schistosomiasis endemic communities and public health professionals. The present review aimed at assessing the evidence/epidemiology of FGS among women/girls in Tanzania. Furthermore, the review assessed the availability of information, published literature on FGS including comorbidities that address FGS in Tanzania mainland and Zanzibar islands. The evidence generated was important to inform the need to address FGS key gaps among researchers, healthcare workers and communities. Overall, the findings indicated that the knowledge of FGS was lacking among the endemic communities and healthcare workers. Findings from this review have shown the available gaps in literature on FGS in Tanzania, from very few community-and-hospitals based studies reported from mainland Tanzania, and Zanzibar. To address this gap, further research is essential to understanding the true burden of disease-associated morbidity, to assessing the impact of single dose praziquantel in FGS lesions, to understanding mental health in relation to FGS, and to integrating delivery of FGS related services in primary health care systems. [ABSTRACT FROM AUTHOR]

Schistosomiasis and soil-transmitted helminthiasis remain a public health concern in Tanzania. This study investigated the prevalence and intensities of Schistosoma haematobium, S. mansoni, and soil-transmitted helminths and associated factors in Itilima district, north-western Tanzania. A cross-sectional survey was conducted between August and September 2020 among 3779 primary schoolchildren in 62 primary schools and 1122 adults in 19 villages. Urine samples were obtained from each participant and examined visually for the presence of macrohaematuria, microhaematuria, and S. haematobium eggs using a urine dipstick and urine filtration test. A single stool sample was obtained from each participant and screened for S. mansoni and soil-transmitted helminths using the Kato Katz and formalin-ether concentration techniques. A questionnaire was administered to schoolchildren to elucidate the risk factors for schistosomiasis. The overall prevalence of S. haematobium in adults was 8.1% (95% confidence interval (CI), 6.6–9.8%). In total, 3779 schoolchildren had complete results from urine testing, and the overall prevalence of S. haematobium was 10.1% (95% CI, 9.1–11.1%). The prevalence of S. mansoni and soil-transmitted helminths was relatively low among both children and adults compared to S. haematobium. Factors associated with S. haematobium infection among schoolchildren were the mother's occupation, children aged 11–15 years, and water contact behaviour. The odds of having schistosomiasis infection among children aged 11–15 are 40% higher than those aged 5–10 (95% confidence interval (CI), 10–80%, p = 0.04). Children of parents who are livestock keepers have 12.3 times higher odds of having infection compared to those who have small-scale businesses (95% CI, 1.0–5.4, p = 0.03). Children who are in contact with infested water more than three times a week have 2.1 times higher odds of having an infection compared to those who do not (95% CI, 2.1; 1.6–2.8, p < 0.001). The findings provide updated geographical information on prevalence, yielding insights into the planning and implementation of mass drug administration in rural Tanzania. [ABSTRACT FROM AUTHOR]