Prevalence and distribution of <i>Schistosoma haematobium</i> infection among school children living in southwestern shores of Lake Malawi

Abstract

BackgroundThe prevalence of Schistosoma haematobium infection has been shown to be about 23.7% among children living in the lakeshore areas of Malawi, with reinfection rates of about 30% to 40%. This study aimed to determine the current prevalence and distribution of S. haematobium infection in school children along the southwestern shores of Lake Malawi and examine the control interventions present in the area. MethodsThis prospective cross-sectional study was conducted in primary schools. School children were enrolled, demographic data were collected, and urine samples were submitted for analysis on macrohaematuria, microhaematuria, and S. haematobium eggs. A questionnaire was administered to 3 health facilities on diagnosis and treatment of schistosomiasis, as well as the control interventions against it. ResultsFour hundred children (174 males and 226 females) were enrolled from 7 primary schools. Mean participant age was 9.57 years (range 7 to 12 years). Fifty children (12.5%) had S. haematobium eggs detected in their urine, with the mean egg count being 15/10 mL. The highest infection intensity category (≥ 50 eggs/10mL) was seen in 10 children (2.5%). Prevalence varied significantly between the schools, with rates ranging from 0% to 20%. Schools with higher prevalence rates were located farther away from the nearest public hospital that provides treatment free of charge. Prevalence correlated with previous history of mass chemotherapy in schools. Mass chemotherapy, health education, and improved water supply and sanitation were some of the interventions that contributed to lower prevalence rates in some areas. ConclusionsSchistosomiasis prevalence around southwestern Lake Malawi was lower than previously reported, owing to control interventions focusing on health education, improved water supply, sanitation, and mass chemotherapy. Consistent and uniform interventions can reduce prevalence further and sustain control. As prevalence falls, diagnostics can identify high transmission areas, monitor disease trends, and guide evidence-based control strategies.

An Assessment of Implementation of Mass Drug Administration for Prevention and Control of Schistosomiasis and Soil-Transmitted Helminths in Selected Southern Malawi Districts

“…These districts are also amongst the high transmission areas with considerable prevalence of infection for both schistosomiasis and STH in Malawi [5][6][7][8][9][10][11][12][13][14][15][16][17].…”

“…Various surveys carried across the country dating from 1994 to 2018 show that schistosomiasis and STH are major public health problems with prevalence ranges of between 50.0%-94.9% for urinary schistosomiasis caused by Schistosoma haematobium, 34.0%-67.0% for intestinal schistosomiasis caused by Schistosoma mansoni and 0.3%-3.9% for STH mainly Ascaris lumbricoides (roundworms) and Ancylostoma sp. (hookworms) [5][6][7][8][9][10][11][12][13][14][15][16][17]. MDA is one of the community-based interventions, which has been widely carried out annually since 2012 [18].…”

An outbreak of intestinal schistosomiasis, alongside increasing urogenital schistosomiasis prevalence, in primary school children on the shoreline of Lake Malawi, Mangochi District, Malawi

“…In Mangochi District, Malawi, the prevalence of Schistosoma haematobium infection in school children warrants preventive chemotherapy. This is achieved by annual mass drug administration (MDA) of praziquantel [2] as provided by the Malawi National Schistosomiasis and Soil-Transmitted Helminthiasis Control Programme (https://www.health.gov.mw/index.php/schistosomiasis-sth-control-programme). MDA is typically guided upon country-wide mapping information which is usually developed from inspection of five schools per district [3].…”

An outbreak of intestinal schistosomiasis, alongside increasing urogenital schistosomiasis prevalence, in primary school children on the shoreline of Lake Malawi, Mangochi District, Malawi

“…In Mangochi District, Malawi, the prevalence of Schistosoma haematobium infection in school children warrants preventive chemotherapy. This is achieved by annual mass drug administration (MDA) of praziquantel [2] as provided by the Malawi National Schistosomiasis and Soil-Transmitted Helminthiasis Control Programme (https://www.health.gov.mw/index.php/schistosomiasis-sth-control-programme).…”