Recent trends in the prevalence and distribution of schistosomiasis in the Nile delta region.

In 1983, a survey of 71 villages in the Nile delta demonstrated that the overall prevalence of Schistosoma mansoni and S. haematobium infections was 39% and 5%, respectively. Recent increased availability of praziquantel, combined with Egyptian Ministry of Health-sponsored media efforts to educate the public about schistosomiasis, prompted us to determine the current status of S. mansoni and S. haematobium infections in the delta and evaluate any changes that may have occurred since the previous survey. The same villages that participated in the 1983 survey were resampled in 1990. Stool and urine samples were requested from all occupants over the age of two years in a 5% sample of houses within each village. Stool (Kato) thick smears and urine sediments were read qualitatively at the rural health station. Field-prepared Kato smears and a 20% sample of urine specimens were forwarded to the Ministry of Health Laboratory, where quantitative readings were also performed. Analysis of samples obtained from 17,310 persons revealed that S. mansoni prevalence had decreased to 23% and that S. haematobium prevalence had decreased to 3% (P < 0.001). The highest levels of schistosome infection were found in governates located in the eastern section of the delta. The observed changes in the prevalence of S. mansoni and S. haematobium suggest that control measures are having a favorable impact on schistosomiasis transmission in this region.

Changes in antischistosomal drug usage patterns in rural Qalyubia, Egypt.

To investigate the usage of antischistosomal drugs in the Nile Delta, an antischistosomal drug history was obtained by interview from a sample of inhabitants of the villages of Halaba (1,024, or every 4th household) and Kharkania (505, or every 20th household), south-central Nile Delta. Only 3% and 0.4% of participants, respectively, in the 2 villages reported receiving antischistosomal drugs during the previous 4 years. Most villagers received oral compounds (praziquantel and niridazole), and the treatment regimen was completed by 95%. This study reveals changes in antischistosomal drug usage since a study 8 years earlier in the village of Halaba, when most of the drugs were injectable compounds.