Ultrasonographical assessment of morbidity in schistosomiasis mansoni in Madagascar: a community-based study in a rural population.
Between June and November 1993, a parasitological, clinical and ultrasonographical survey was carried out in the mid west of Madagascar, among the whole population of a village where Schistosoma mansoni was endemic. S. mansoni eggs were found in the stools of 61.8% of the 544 individuals examined; the highest prevalence of infection (85.7%) was observed in the 15-19 years old age group. The most intense infections were recorded in the 10-14 years age group, in which the geometric mean egg count was 265 eggs/g of faeces and 34.3% of the individuals excreted more than 400 eggs/g. The egg count decreased steadily from the age of 15 years. Ultrasonographical examination was performed in 482 inhabitants older than 2 years: 29% of them presented definite schistosome associated liver alterations according to the proposals for staging S. mansoni infection made by the World Health Organization Cairo working group. Stage 3 was never observed in subjects under 30 years old. This is consistent with the need for a long-standing infection before serious lesions occur. A significant relationship between egg count and degree of liver alterations was found only in the 20-29 years age group.
Boisier
P
P
Institut Pasteur de Madagascar, Antananarivo.
Serieye
J
J
Ravaoalimalala
V E
VE
Roux
J
J
Esterre
P
P
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D002648:Child; D002675:Child, Preschool; D005243:Feces / Q000469:parasitology; D005260:Female; D006801:Humans; D008109:Liver Diseases, Parasitic / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000473:pathology; D008270:Madagascar / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D010270:Parasite Egg Count; D012423:Rural Health; D012555:Schistosomiasis mansoni / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000473:pathology; D017678:Sex Distribution; D014463:Ultrasonography