The capybara (Hydrochaeris hydrochaeris) is a large rodent used for human consumption in certain areas of South America. In the present study, viable Toxoplasma gondii was isolated for the first time from this host. Antibodies to T. gondii were assayed in the sera of 64 capybaras from 6 counties of São Paulo State, Brazil, using the modified agglutination test (MAT, [greater or equal]1:25 dilution) and the indirect fluorescent antibody test (IFAT, [greater or equal]1:16 dilution), and antibodies were found in 48 (75%) by MAT, and 49 (76.6%) by IFAT. Samples of brain, heart, and tongue of 40 seropositive capybaras were pooled, digested in pepsin, and bioassayed in mice. Toxoplasma gondii was isolated from tissue homogenates of 36 capybaras, and the isolates were designated TgCyBr1-36. Most isolates were lethal to mice; 17 of the 36 isolates killed 100% of infected mice, 11 isolates caused mortality in 25-90% of infected mice, and 8 isolates were nonpathogenic to mice. Results indicate that asymptomatic capybaras can harbor mouse-virulent T. gondii, and hence they can serve as a source of infection for humans. Toxoplasma gondii can infect almost all warm-blooded animals, including humans (Dubey and Beattie, 1988). Humans become infected postnatally by ingesting tissue cysts from undercooked meat, consuming food or drink contaminated with oocysts, or by accidentally ingesting oocysts from the environment. The capybara (Hydrochaeris hydrochaeris) is an herbivorous rodent spread throughout tropical South America. Capybara meat is consumed by humans in many countries, and it could be considered a source of T. gondii if insufficiently cooked meat is ingested. We previously reported antibodies to T. gondii in capybaras from Brazil (Cañón-Franco et at., 2003). In the present study, we report isolation of viable T. gondii for the first time from this hos
To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.