Endemic status of urogenital schistosomiasis and the efficacy of a single-dose praziquantel treatment in unmapped rural farming communities in Oyo East Local Government Area, Oyo State, Nigeria

Abstract

Background: Schistosomiasis is endemic in Nigeria, and the treatment is largely concentrated on children enrolled in schools. Consequently, the coverage of non-enrolled school-aged children is often neglected. Ajagba and Awosan are two communities in Nigeria that have never had any control intervention. Hence, this survey was designed to determine the endemicity of urogenital schistosomiasis and to evaluate the efficacy of a single-dose praziquantel in the communities.

Methods: Urine sample (10 mL) of each participant from Ajagba and Awosan communities was filtered through 12μm polycarbonate filter. The filter was placed on a microscope slide, and stained with a drop of 1% Lugol iodine solution. The stained slides were examined under the microscope and the numbers of S. haematobium eggs were counted. Water contact sites were searched for snail hosts and the snails collected were shed for Schistosoma cercariae. Data were analyzed using SPSS version 24.0 and the significance level was set at 95%.

Results: The overall prevalence of infection in the Ajagba community was 45.6% with a mean intensity of 61.1 ± 144.5 eggs/10 mL of urine, while the prevalence of infection in the Awosan community was 5.7% with a mean intensity of 1.4 ± 6.8 eggs/10 mL of urine. The school-aged children had a prevalence and mean intensity of infection of 73.1% and 111.6 ± 177.9 eggs/10 mL of urine, respectively. Following treatment, women had a higher egg reduction rate than men (p = 0.0283). Bulinus globosus were found in Ajagba but not in Awosan, with 5.7% shedding Schistosoma spp, cercariae.

Conclusion: Urogenital schistosomiasis was hyperendemic in the Ajagba community, and hypoendemic in the Awosan community. The presence of Bulinus globosus supported the transmission of the schistosomiasis in the Ajagba community. Communities where schistosomiasis is still actively transmitted in Nigeria should be identified for effective intervention through the MDA programs.

Fig 1. Map showing the Ajagba and the Awosan communities in Oyo East Local Government Area.

The map was created in the ArcGIS software program, and the source of the basemap shapefile was the U.S. Geological Survey (USGS). Base layer of the map: https://www.openstreetmap.org/#map=6/9.117/8.674.

Fig 2. The categories of intensities at the baseline and the post-treatment surveys in the Ajagba community.

Fig 3. The mean intensities of infection at the baseline and the post-treatment surveys in the Ajagba community by sex.

Fig 4. Prevalence of microhematuria, proteinuria and leukocyturia among participants at the Ajagba and the Awosan communities.