Prevalence, risk factors, and clinical manifestations of schistosomiasis among school children in the White Nile River basin, Sudan

Abstract

Background: We investigated the prevalence, risk factors, and clinical manifestations of schistosomiasis in White Nile State, Sudan, to determine the local characteristics of schistosomiasis in the White Nile River basin.

Methods: Urine and stool samples were collected from 338 students (176 boys, 162 girls) at three primary schools and were examined using the urine filtration method and the Kato-Katz technique, respectively. Of the students, 200 were interviewed using a semi-structured questionnaire to assess water-contact patterns and health conditions related with urinary schistosomiasis.

Results: Of the 338 students, egg-positive rates for S. haematobium and S. mansoni were 45.0% and 5.9%, respectively, and 4.4% were mixed. The intensities of S. haematobium and S. mansoni infection were 1.091 ± 0.744 log EP10 (eggs per 10 mL of urine, mean ± SD = 57 ± 172 EP10) and 1.787 ± 0.844 log EPG (eggs per gram of stool, mean ± SD = 156 ± 176 EPG), respectively. The prevalence and intensity of S. haematobium infection differed significantly among the three schools, but not by gender or age. Urinary schistosomiasis was significantly associated with the frequencies of contaminated water contact, taking baths, swimming, and wading the stream; however, frequencies of these events were not significantly correlated with infection intensity. Self-reported hematuria and dysuria also correlated significantly with urinary schistosomiasis.

Conclusions: The overall prevalence of schistosomiasis, especially urinary schistosomiasis, is high in the White Nile River basin, Sudan, and is closely associated with frequencies of water contact, taking baths, swimming, and wading the stream. We strongly recommend implementation of an integrated schistosomiasis control program in this area.

Figure 1

Location of study areas in the White Nile River basin, White Nile State, Sudan. The colored area indicates White Nile State, Sudan. The White Nile River runs inside the state and crosses the whole state.

Figure 2

Positive rates of Schistosoma haematobium and/or S. mansoni infections and hematuria. Of the 338 students, 46.5% were infected by S. haematobium or S. mansoni, and 4.4% had mixed infections. The egg-positive rates for S. haematobium and S. mansoni were 45.0% and 5.9%, respectively. Hematuria was seen in 5.0% of the students.