title: Seroprevalence of infection with Toxoplasma gondii in indigenous Brazilian populations.
abstract: The prevalence of Toxoplasma gondii in indigenous Brazilian tribes with different degrees of acculturation was studied in the Enawenê-Nawê, an isolated tribe, in the state of Mato Grosso, the Waiãpi, with intermittent non-Indian contacts, in the state of Amapa, and the Tiriyó, with constant non-Indian contacts, in the state of Para. An IgG-enzyme-linked immunosorbent assay (IgG-ELISA) or an IgG/IgM-indirect immunofluorescence antibody (IFA) assay were performed for the detection of antibodies to T. gondii in 2000-2001. Both assays showed that the Tiriyó had the lowest crude seroprevalence (55.6%), the Enawené-Nawé the highest crude seroprevalence (80.4%), and the Waiãpi an intermediate crude seroprevalence (59.6%). The age-adjusted prevalence (95% confidence intervals) values for the Tiriyó, Enawenê-Nawê, and Waiãpi were 57.3% (53.4, 61.1%), 78.8% (72.2, 85.7%), and 57.7% (52.5, 62.9%), respectively. Contact with non-Indians probably did not influence the prevalence of the infection. However, differential contact with soil-harboring oocysts from wild felines may be responsible for the various seroprevalences in the different tribes.
authors.affiliation: Department of Protozoology, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro, Brazil.
authors.forename: Cleide A
authors.initials: CA
authors.lastname: Sobral
authors.forename: Maria Regina R
authors.initials: MR
authors.lastname: Amendoeira
authors.forename: Antonio
authors.initials: A
authors.lastname: Teva
authors.forename: Balmukund N
authors.initials: BN
authors.lastname: Patel
authors.forename: Carlos H
authors.initials: CH
authors.lastname: Klein
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood*; D001938:Brazil / Q000453:epidemiology; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007075:Immunoglobulin M / Q000097:blood; D016036:Seroepidemiologic Studies; D017678:Sex Distribution; D014122:Toxoplasma / Q000276:immunology*; D014123:Toxoplasmosis / Q000175:diagnosis / Q000453:epidemiology*
chemical_list: D000913:Antibodies, Protozoan; D007075:Immunoglobulin M