EPIDEMIOLOGIC STUDIES ON SCHISTOSOMA-MANSONI INFECTION IN THE WESTERNREGION OF SAUDI-ARABIA USING THE POTASSIUM HYDROXIDE STOOL DIGESTION TECHNIQUE

The potassium hydroxide stool digestion technique was used in 30 sites in the Western Region of Saudi Arabia (Hijaz highlands and Tihamah lo wlands) for epidemiological studies of S. mansoni. The mean prevalence rate in 2792 individuals (1490 males and 1302 females) in Hijaz highl ands (20 sites) was 6.09 (0.5-20.1%) and the geometric mean egg count of stool was 110.8 (63-285). The prevalence rate was greater in males (8.06%) than in females (3.79%). The peak prevalence in males was in t he age group 11-15 years, and 31-50 years in females. In 10 sites in t he Tihamah lowlands a total of 1771 persons were examined for schistos omiasis. Only one site was recorded with S. mansoni, at a prevalence r ate of 0.05%; S. haematobium was recorded in two sites at prevalence r ates of 0.55 and 1.13%. Praziquantel therapy (40 mg kg(-1)) of 170 S. mansoni cases showed a cure of 85-98% at 1-6 months after treatment an d a considerable reduction in stool arithmetic mean egg count. Schisto soma haematobium was not recorded in the Hijaz highlands.