The epidemiology of schistosomiasis in the later stages of a control programme based on chemotherapy: the Basrah study. 1. Descriptive epidemiology and parasitological results.

The association between infection with Schistosoma haematobium and various factors including water contact pattern, past history of haematuria and treatment for schistosomiasis and cercarial dermatitis was investigated in Southern Iraq. The study covered mainly primary schoolchildren in different areas of Basrah and in Al-maadan locality where the majority of households with infected schoolchildren occurred. Urine examination was by the sedimentation and Nuclepore filtration methods. S. haematobium infection was very focal in distribution. There was evidence of local transmission in the Al-maadan locality, while in Abu-al-Jawzi schistosomiasis might have been acquired from endemic areas outside Basrah governorate. Swimming, history of haematuria, and history of treatment of schistosomiasis were significantly associated with the level of infection determined by egg count. Cercarial dermatitis, and bathing, washing clothes and fetching water were not significantly associated. The prevalence of infection among male members of households of infected children was significantly higher than that among male members of the remaining households in Al-maadan. There was no evidence of clustering of cases at household level. The implications of these findings for control and for future research on schistosomiasis in Basrah are discussed.