Occurrence of Toxoplasma gondii antibodies in birds from the Atlantic Forest, state of São Paulo, Brazil

Avian are considered important intermediate hosts for Toxoplasma gondii because they serve as source of infection for Felidae, which shed environmentally resistant oocysts after ingesting infected tissues. Little is known of epidemiology of toxoplasmosis in wild birds. In the present study, antibodies to T. gondii were determined in 202 wild birds of 37 species captured in seven small areas of the Atlantic Forest, in the state of São Paulo, Brazil, and provided information on possible associated risk factors. Antibodies to T. gondii were assayed by the modified agglutination test (MAT) and found in 73 (36.1%) of 202 birds with titers of 1:5 in 16 samples, 1:10 in 26 samples, 1:20 in 17 samples, 1:40 in 10 samples, 1:80 in three samples, and 1:160 in one sample. No association was observed between T. gondii seropositivity and the local where the birds were collected. Seropositivity was higher in birds that lived on the forest floor (p < 0.001; U = 1230.0), and in omnivorous birds (p = 0.007; U = 3939.0). T. gondii antibodies were reported for the first time in 23 species of birds enlarging the host range of this parasite. Notably, T. gondii antibodies were found in 83.3% (15/18) of the Rufous-bellied Thrush (Turdus rufiventris).