Schistosomiasis outbreak investigation - Bokomu District, Gbarpolu County, Liberia, 2016

Introduction : schistosomiasis is an acute and chronic disease caused by parasitic worm Schistosoma. There are urogenital and intestinal forms of schistosomiasis, leading to chronic ill-health, anaemia and end-organ damage, including renal failure. Transmission is by contact with water infested by infected water snail. Schistosoma haematobium and Schistosoma mansoni are prevalent in Liberia. On August 23, 2016, the Bokomu District Health Team received reports of increased cases of haematuria in Gbarnga, Bokomu District from a community volunteer after two suspected cases from the community reported to the hospital. We investigated to confirm the outbreak, identify the causative agent, determine the extent of the disease, and identify the source of transmission and to control the spread. Methods : the total population of Gbarnga community was 2,100. We screened community members who availed themselves by conducting laboratory testing of their urine samples. We conducted an environmental assessment of water bodies. We analyzed the data using Microsoft Excel. Results : of 256 persons screened, 96% (247) tested positive for S. haematobium. More community members declined to report for screening although some were symptomatic. Median age of screened persons was 14 (range 1.8 to 43years). Majority (64%) of these were of school-going age. Duration of symptoms ranged from 1 week to 3 years. The main source of water is a swamp; for bathing, farming activities and recreational swimming. We observed some water snails around the swamp but could not test the water for cercaria worms. Conclusion : an outbreak of urinary schistosomiasis was confirmed, caused by S. haematobium. Prevalence was at least 11.8% (247 out of 2100). The community swamp was the likely reservoir of the infection. The County Health Team conducted mass education and treatment and recommended that the Government provide the community with potable water. Surveillance is ongoing.