Spread of schistosomiasis mansoni to middle and upper Egypt

ABSTRACT

Following the construction of Aswan High Dam, Schistosoma mansoni seems to be a growing problem and may be replacing S. hematobium along the River Nile in Egypt. This is due to relative increase of the snail vector of S. mansoni Biomphalaria alexandrina compared with the reduction of the snail vector of S. hematobium Bulinus truncatus. This retrospective study presented the results of cases of S. mansoni diagnosed in four schistosomiasis research projects performed in Middle and Upper Egypt. S. mansoni was detected in 103 out of 29683 subjects studied in these four studies. It was also detected in 35 out of 93 villages and satellites screened. S. mansoni ova were detected in urine of 14 out of 9555 in Assiut and in 9 out of 12327 in Qena. It was detected in both urine and stool in three cases. Sixty-six of the cases were among the age group below twenty years. Most of the cases had mild infection with ova <50 ova/g. It was concluded that this retrospective study showed that the spread of S. mansoni to Middle and Upper Egypt seems to be progressive and not in limited foci as reported before and it was detected in 40% of the villages screened. Further prospective epidemiological studies are recommended to evaluate and investigate this serious phenomenon