The potential of an immunofluorescence test for detection of IgM
antibodies against Schistosoma mansoni gut-associated antigens
(IgM-IFT) was evaluated as a tool for studying aspects related to the
schistosomiasis transmission in Ribeirão Pires, in the
metropolitan area of the capital of the State of São Paulo,
Brazil. Children from a school with about 400 students, 6 to 18 years,
were followed-up for two years. In the five surveys, carried out at
6-month intervals, from October 92 to October 94, serological
(IgM-IFT) prevalence indices of 5.3%, 5.8%, 6.2%, 2.9% and 3.3% were
obtained. These indices were 7 to 10 times higher than the
parasitological prevalence indices of 0.5%, 0.5%, 0.7%, 0.4% and 0%
determined by the Kato-Katz method. Seroconversion from IFT negative
to positive was indicating possible newly acquired S. mansoni
infection in three children. But confirmation of infection by fecal
examination was possible in only one child. The IgM-IFT can constitute
a valuable tool for the improvement of the vigilance program in low
endemic areas for schistosomiasis, better characterizing the S.
mansoni transmission in such areas.
