IgM-immunofluorescence test as a diagnostic tool for epidemiologic studies of Schistosomiasis in low endemic areas.
The high sensitivity and the ability to diagnose schistosomiasis in a very early phase after infection have indicated the detection of IgM antibodies to Schistosoma mansoni gut antigens by the immunofluorescence test (IgM-IFT) as a useful serological test for epidemiological studies in low endemic areas. When applied in a follow-up study for two years, higher rates of seroconversion from IFT negative to positive were observed during the summer months, suggesting seasonal transmission of schistosomiasis in the rural area of the municipality of Itariri (São Paulo, Brazil). In each survey, blood samples from about 600 schoolchildren were collected on filter paper and submitted to IgM-IFT. When the blood samples were classified for the IgM antibody levels, according to the intensity of fluorescent reaction observed at fluorescence microscopy, and correlated to the egg counts in the Kato-Katz positive patients, no association was observed. This observation might suggest that the intensity of fluorescence observed in the IgM-IFT, as an indicator of IgM antibody levels, could not be an useful seroepidemiological marker for classifying areas of low endemicity according to degrees of infection.
Departamento de Biologia, Universidade de Taubaté, Taubaté, SP, 12030-010, Brasil. kanamura@usp.br
Herminia Yohko
HY
Kanamura
Rita Maria da
RM
Silva
Silvia Gabriel
SG
Chiodelli
Carmen Moreno
CM
Glasser
Luiz Candido de Souza
LC
Dias
D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood*; D000947:Antigens, Helminth / Q000097:blood; D015415:Biomarkers / Q000097:blood; D001938:Brazil / Q000453:epidemiology; D002648:Child; D005455:Fluorescent Antibody Technique / Q000379:methods*; D006801:Humans; D007075:Immunoglobulin M / Q000097:blood*; D015995:Prevalence; D012424:Rural Population; D012550:Schistosoma mansoni / Q000276:immunology*; D012555:Schistosomiasis mansoni / Q000175:diagnosis* / Q000453:epidemiology; D012680:Sensitivity and Specificity; D016036:Seroepidemiologic Studies; D012720:Severity of Illness Index
D000909:Antibodies, Helminth; D000947:Antigens, Helminth; D015415:Biomarkers; D007075:Immunoglobulin M