The infection rates of trypanosomes in squirrel monkeys at two sites in the Brazilian Amazon.
A study was conducted to determine the prevalence of natural infections by trypanosome species in squirrel monkeys: Saimiri sciureus (Linnaeus) and Saimiri ustus (Geoffroy) caught respectively near 2 hydroelectric plants: Balbina, in the State of Amazonas, and Samuel, in the State of Rondônia, Brazil. A total of 165 squirrel monkeys were examined by thick and thin blood smears (BS), haemocultures and xenodiagnosis: 112 monkeys, 67.9% (being 52.7% with mix infections) were positive to trypanosomes. Four species of trypanosomes were found in monkeys from the 2 areas: Trypanosoma (Tejeraia) rangeli Tejera or T. rangeli-like parasites in 58 squirrel monkeys (35.2%), Trypanosoma (Megatrypanum) minasense Chagas in 55 (33.3%), Trypanosoma (Herpetosoma) saimirii Rodhain or T. saimirii-like parasites in 53 (32.1%) and Trypanosoma (Schizotrypanum) cruzi Chagas in 17 (10.3%). As T. saimirii resembles T. minasense in blood-stream trypomastigotes and T. rangeli in cultural forms and in this survey almost all monkeys presenting trypanosomes morphologically indistinguishable from T. saimirii and/or T. minasense in BS were found through xenodiagnosis and/or haemoculture to be infected by T. rangeli, we suggest that the validity of T. saimirii needs to be evaluated.
Ziccardi
M
M
Laboratório de Transmissores de Hematozoários, Instituto Oswaldo Cruz, Rio de Janeiro, Brasil.
Lourenço-de-Oliveira
R
R
D000818:Animals; D001938:Brazil / Q000453:epidemiology; D015994:Incidence; D015995:Prevalence; D012453:Saimiri / Q000469:parasitology*; D014345:Trypanosoma / Q000145:classification*; D014352:Trypanosomiasis / Q000453:epidemiology / Q000662:veterinary*