Effect of human immigration on the age distribution of schistosome infections in Siavonga community, Lake Kariba, Zambia.
A study on the distribution of schistosomiasis in the community at Siavonga revealed Schistosoma haematobium infection in 35.5% of 338 subjects and a geometric mean egg count (GMEC) and (S.D.) of 13.7 (7.2) eggs/10 ml urine. The prevalence of S. mansoni infection among 323 subjects was 60.1%, with a GMEC of 336.8 (4.8) eggs/g stool. Among the infected, 69.5% carried both schistosome species. Although prevalence of infection with either species was highest in those aged 10-14 years, high prevalences of infection were found in older age groups and egg intensities were uniformly distributed throughout all age-groups. The observed diversion from the typically age-dependent distribution of schistosome infections probably reflects exposure to infection relatively late in life, as the result of immigration from non-endemic areas.
Mungomba
L M
LM
Department of Biological Sciences, University of Zambia, Lusaka. lmungomba@natsci.unza.zm
Chandiwana
S K
SK
Sukwa
T Y
TY
Marshall
I
I
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D002648:Child; D002675:Child, Preschool; D004641:Emigration and Immigration; D005260:Female; D006801:Humans; D008297:Male; D015995:Prevalence; D012553:Schistosomiasis haematobia / Q000150:complications / Q000453:epidemiology* / Q000635:transmission; D012555:Schistosomiasis mansoni / Q000150:complications / Q000453:epidemiology* / Q000635:transmission; D015024:Zambia / Q000453:epidemiology