Dw. Meyrowitsch et al., BANCROFTIAN FILARIASIS - ANALYSIS OF INFECTION AND DISEASE IN 5 ENDEMIC COMMUNITIES OF NORTH-EASTERN TANZANIA, Annals of tropical medicine and parasitology, 89(6), 1995, pp. 653-663
Clinical and parasitological surveys for bancroftian filariasis were c
arried out in five endemic communities in north-eastern Tanzania, cove
ring a population of 3086 individuals. High microfilarial (mf) prevale
nces (17.7%-34.7%) and mf geometric mean intensities (251-1122 microfi
lariae/ml) were observed in the communities. The mf prevalence general
ly increased with age, but often levelled out in the older age groups.
Larger variability was observed in individual mf intensities and no d
ear association between mf geometric mean intensity and age or sex was
seen. Hydrocele was the most common clinical manifestation (with a pr
evalence of 30.2%-40.0% in male subjects aged greater than or equal to
20 years) followed by leg elephantiasis (with a prevalence of 2.0%-6.
8% in all subjects aged greater than or equal to 20 years). In four of
the five communities, there was no significant difference in mf preva
lence in males aged greater than or equal to 20 years between those wi
th and without hydrocele. In all the communities, the mf geometric mea
n intensities in microfilaraemic males with and without hydrocele were
not significantly different. The present study therefore did not indi
cate any association between hydrocele in males (the most common type
of chronic clinical manifestation seen) and presence or absence of mic
rofilaraemia. In contrast, only two (4.4%) of the 45 subjects with leg
elephantiasis were microfilaraemic. In children aged 1-15 years, mf p
revalence was significantly higher among those with microfilaraemic mo
thers (18.0%) than among those with amicrofilaraemic mothers (7.9%). T
he children of microfilaraemic mothers were therefore at 2.3-fold high
er risk of becoming microfilaraemic than the children of amicrofilarae
mic mothers. No relationship between the mf prevalence of the children
and the mf status of their fathers was observed.