Schistosomiasis remains one of the most prevalent neglected tropical diseases in Tanzania. World Vision Tanzania, in collaboration with the Ministry of Health through the National Neglected Tropical Diseases Control Programme, implemented school- and community-based mass drug administrations, community-led total sanitation, and community voice and action from 2020 to 2022. This study assessed changes in the prevalence of schistosomiasis in the Itilima district of northwestern Tanzania following the implementation of these integrated interventions. A total of 1,405 students from 22 schools participated in the baseline survey in August to September 2020, and 1,320 in September 2022. Additionally, 368 adults from 8 villages participated in the baseline survey, and 401 in the endline survey. The prevalence difference was calculated to assess changes before and after the integrated interventions. We also investigated risk factors for Schistosoma haematobium infection using endline data. The prevalence difference between 2020 and 2022 was -20.0% (95% confidence interval (CI)=-22.2%–-17.7%, p<0.001) for students and -19.6% (95% CI=-22.2%–-17.7%, p<0.001) for adults. Individuals without a latrine were more likely to have schistosomiasis (adjusted odds ratio=5.9, 95% CI=1.7–21.5, p=0.01) compared to those who had a latrine. The findings indicate substantial changes in schistosomiasis prevalence in the study area following the implementation of integrated interventions. To sustain these achievements in Itilima, a multi-sectorial approach is highly recommended to integrate additional measures for eliminating schistosomiasis as a public health problem.
In several schistosomiasis-endemic countries, the prevalence has remained high in some areas owing to reinfection despite repeated mass drug administration (MDA) interventions; these areas are referred to as persistent hot spots. Identifying hotspots is critical for interrupting transmission. This study aimed to determine an effective means of identifying persistent hot spots. First, we investigated the differences between Schistosoma haematobium and Schistosoma mansoni prevalence among school-aged children (SAC) estimated by a community-based survey, for which local key informants purposively selected communities, and a randomly sampled school-based survey. A total of 6,225 individuals residing in 60 villages in 8 districts of North Kordofan, Blue Nile, or Sennar States, Sudan participated in a community-based survey in March 2018. Additionally, the data of 3,959 students attending 71 schools in the same 8 districts were extracted from a nationwide school-based survey conducted in January 2017. The community-based survey identified 3 districts wherein the prevalence of S. haematobium or S. mansoni infection among SAC was significantly higher than that determined by the randomly sampled school survey (e.g., S. haematobium in the Sennar district: 10.8% vs. 1.1%, P<0.001). At the state level, the prevalence of schistosomiasis among SAC, as determined by the community-based survey, was consistently significantly higher than that determined by the school-based survey. Purposeful selection of villages or schools based on a history of MDA, latrine coverage, open defecation, and the prevalence of bloody urine improved the ability for identifying persistent hot spots.
Global efforts to identify groups at high risk for schistosomiasis have mainly concentrated on identifying their geographical distribution. Investigations on the socioeconomic characteristics of high-risk groups are relatively scarce. This study aimed to explore the associations between schistosomiasis among students and their parents’ occupations. A nationwide cross-sectional survey was conducted targeting 105,167 students in 1,772 primary schools across Sudan in 2017. From these students, 100,726 urine and 96,634 stool samples were collected to test for Schistosoma haematobium and S. mansoni infection. A multi-level mixed effect analysis was used with age and sex as fixed factors, and school as a random factor. The odd ratios (ORs) of practicing open defecation among farmers’ children were almost 5 times higher than their counterparts whose parents were government officials (OR=4.97, 95% confidence intervals (CIs): 4.57-5.42, P<0.001). The ORs of contacting water bodies for watering livestock among farmers’ children were more than 4 times higher than those of children whose parents were government officials (OR=4.59, 95% CIs: 4.02-5.24, P<0.001). This study shows that schistosomiasis represents a disease of poverty and that farmers’ children constituted a high-risk group.
Citations
Citations to this article as recorded by
Using zero-inflated and hurdle regression models to analyze schistosomiasis data of school children in the southern areas of Ghana Kojo Nketia, Dziedzom K. de Souza, Jean Coulibaly PLOS ONE.2024; 19(7): e0304681. CrossRef
Prevalence and Risk Factors of Schistosomiasis in Sudan: A Systematic Review and Meta-Analysis Yousef Alsaafin, Ayman Omer, Osama Felemban, Sarra Modawi, Maydolin Ibrahim, Abdullah Mohammed, Ammar Elfaki, Ahmed Abushara, Maryam A SalahEldin Cureus.2024;[Epub] CrossRef
Identifying the risk factors of schistosomiasis in Indonesia Christine Christine, Herlina Susanto Sunuh, Fellysca Veronica Margareth Politon, Diana Vanda Daturara Doda Healthcare in Low-resource Settings.2023;[Epub] CrossRef
We aimed to explore the population dynamics of snail in 3 sites of the White Nile in Sudan. More specifically, we aimed to investigate the annual patterns of snail populations that act as intermediate hosts of schistosomes and monthly snail infection rates and ecological characteristics presumably related to snail populations. We collected snails for 1 year monthly at 3 different shore sites in the vicinity of El Shajara along the White Nile river in Khartoum State, Sudan. In addition, we measured air and water temperatures, water turbidities, vegetation coverages, and water depths and current speeds. Most of the collected snails were Biomphalaria pfeifferi and Bulinus truncatus. The population densities of snails and their infection rates varied across survey sites. The collected snails liberated S. mansoni and S. haematobium cercariae as well as Amphistome and Echinostome cercariae. Infected snails were found during March-June. The ecological characteristics found to be associated with the absence of snails population were: high turbidity, deep water, low vegetation coverage (near absence of vegetation), high water temperature, and high current speed. To our knowledge, this is the first longitudinal study of the snail population and ecological characteristics in the main basin of the White Nile river.
Citations
Citations to this article as recorded by
Seasonal distribution and cercarial shedding of Bulinus spp. snails: Implications for urogenital schistosomiasis control in the Simiyu Region, northwestern Tanzania Nyanda C. Justine, Humphrey D. Mazigo, Antje Fuss, Bonnie L. Webster, Eveline T. Konje, Klaus Brehm, Andreas Mueller Current Research in Parasitology & Vector-Borne Diseases.2025; 7: 100248. CrossRef
Freshwater snail-borne parasitic diseases in Africa Papa Mouhamadou Gaye, Souleymane Doucouré, Doudou Sow, Cheikh Sokhna, Stéphane Ranque Tropical Medicine and Health.2024;[Epub] CrossRef
Abundance, Distribution, and Diversity of Freshwater Snail and Prevalences of Their Infection by Cercaria of Fasciola gigantica and Schistosoma spp at Mayo-Vreck River, Far North Region of Cameroon Augustin Siama, Serges Eteme Enama, Justin Kalmobe, Samuel Abah, Angele Foutchou, Alexandre Michel Njan Nloga, Pedro P. Chieffi Journal of Tropical Medicine.2023; 2023: 1. CrossRef
Variation in water contact behaviour and risk of Schistosoma mansoni (re)infection among Ugandan school-aged children in an area with persistent high endemicity Suzan C. M. Trienekens, Christina L. Faust, Fred Besigye, Lucy Pickering, Edridah M. Tukahebwa, Janet Seeley, Poppy H. L. Lamberton Parasites & Vectors.2022;[Epub] CrossRef
The Life Histories of Intermediate Hosts and Parasites of Schistosoma haematobium and Schistosoma mansoni in the White Nile River, Sudan Hassan Ahmed Hassan Ahmed Ismail, Abed el Aziz Abed el Rahim Mohamed Ahmed, Seungman Cha, Yan Jin International Journal of Environmental Research and Public Health.2022; 19(3): 1508. CrossRef
Contrasting epidemiology of urogenital schistosomiasis among pastoral communities surrounding three Ramsar wetland in Nigeria O. G. Ajakaye, A. G. Dagona, A. G. Haladu, A. Ombugadu, M. P. Lapang, E. E. Enabulele Journal of Parasitic Diseases.2022; 46(3): 637. CrossRef
Distribution and seasonal abundance of Biomphalaria snails and their infection status with Schistosoma mansoni in and around Lake Tana, northwest Ethiopia Tamirat Hailegebriel, Endalkachew Nibret, Abaineh Munshea Scientific Reports.2022;[Epub] CrossRef
Transmission Dynamics of Schistosoma haematobium among School-Aged Children: A Cohort Study on Prevalence, Reinfection and Incidence after Mass Drug Administration in the White Nile State of Sudan Yan Jin, Young-Ha Lee, Seungman Cha, In-Uk Choi, Hassan Ahmed Hassan Ahmed Ismail, Mousab Siddig Elhag, Sung-Tae Hong International Journal of Environmental Research and Public Health.2021; 18(21): 11537. CrossRef
Seungman Cha, Sung-Tae Hong, Jin-Su Lee, Hoo Gn Jeong, In-Sun Kwon, Abd Al Wahab Saed, Mousab Siddig Elhag, Hassan Ahmed Hassan Ahmed Ismail, Mutamad Amin, Young-Ha Lee
Korean J Parasitol 2020;58(4):421-430. Published online August 25, 2020
This study aimed to investigate whether mass drug administration (MDA) intervention has an equivalent effect on reducing the prevalence and intensity of Schistosoma haematobium infection regardless of the baseline values. A repeated cross-sectional survey was performed targeting students of 12 primary schools in Al Jabalain and El Salam districts of White Nile State, Sudan, at both 1 week before and 8 months after the MDA. Prior to the baseline survey, school-aged children in Al Jabalain had received MDA interventions twice in 4 years, while those in El Salam had not. The baseline prevalence was 9.1% in Al Jabalain and 35.2% in El Salam, which were reduced to 1.8% and 5.5% at 8 months after the MDA, respectively. The corresponding reduction rates were 80.3% and 84.4%, not significant difference between both districts. However, changes in the geometric mean intensity (GMI) of egg counts were significantly different between both districts. The baseline GMIs were 14.5 eggs per 10 ml of urine (EP10) in Al Jabalain and 18.5 EP10 in El Salam, which were reduced to 7.1 and 11.2 EP10 after treatment, respectively. The corresponding reduction rates were 51.0% and 39.5%. In conclusion, MDA interventions were found to bring about similar relative reduction in prevalence regardless of the baseline value; however, the relative reduction in infection intensity was more salient in the district with a low baseline value for both prevalence and intensity. This clearly points to the importance of repeated MDA interventions in endemic areas, which will eventually contribute to schistosomiasis elimination.
Citations
Citations to this article as recorded by
Prevalence and Risk Factors of Schistosomiasis in Sudan: A Systematic Review and Meta-Analysis Yousef Alsaafin, Ayman Omer, Osama Felemban, Sarra Modawi, Maydolin Ibrahim, Abdullah Mohammed, Ammar Elfaki, Ahmed Abushara, Maryam A SalahEldin Cureus.2024;[Epub] CrossRef
Programmatic Implications for Schistosomiasis Elimination Based on Community-Based Survey in the Blue Nile, North Kordofan, and Sennar States, Sudan Hassan Ahmed Hassan Ahmed Ismail, Seungman Cha, Yan Jin, Sung-Tae Hong Life.2023; 13(4): 1049. CrossRef
Implications for selecting persistent hot spots of schistosomiasis from community- and school-based surveys in Blue Nile, North Kordofan, and Sennar States, Sudan Hassan Ahmed Hassan Ahmed Ismail, Seungman Cha, Yan Jin, Sung-Tae Hong Parasites, Hosts and Diseases.2023; 61(2): 216. CrossRef
Review of Recent Prevalence of Urogenital Schistosomiasis in Sub-Saharan Africa and Diagnostic Challenges in the Field Setting Sung-Tae Hong Life.2023; 13(8): 1670. CrossRef
Investigation of Intestinal and Blood Parasites in People Returning to Turkey with a History of Traveling Abroad During the Pandemic Abdurrahman Ekici, Esra Gürbüz, Ahmet Hakan Ünlü, Rahmi Yıldız, Selahattin Aydemir, Ahmed Galip Halidi, Nuriz Ödemiş, Sinan Karakuş, Şehriban Yürektürk, Mutalip Çiçek, Hasan Yılmaz Turkish Journal of Parasitology.2022; 46(2): 108. CrossRef
Transmission Dynamics of Schistosoma haematobium among School-Aged Children: A Cohort Study on Prevalence, Reinfection and Incidence after Mass Drug Administration in the White Nile State of Sudan Yan Jin, Young-Ha Lee, Seungman Cha, In-Uk Choi, Hassan Ahmed Hassan Ahmed Ismail, Mousab Siddig Elhag, Sung-Tae Hong International Journal of Environmental Research and Public Health.2021; 18(21): 11537. CrossRef
Urinary schistosomiasis and the associated bladder cancer: update Mohamed S. Zaghloul, Tarek M. Zaghloul, Mai K. Bishr, Brian C. Baumann Journal of the Egyptian National Cancer Institute.2020;[Epub] CrossRef
First
Prev
