title: Trypanosoma (Megatrypanum) lainsoni n. sp. from Mesomys hispidus (Rodentia: Echimyidae) in Brazil: trypomastigotes described from experimentally infected laboratory mice.
abstract: We report the detection, isolation and description of Trypanosoma (Megatrypanum) lainsoni n. sp. from a caviomorph rodent, Mesomys hispidus (Rodentia: Echimyidae), obtained in the Rio Negro region of the state of Amazonas, in northern Brazil. Laboratory-bred white mice (Mus musculus) and rats (Rattus rattus) were inoculated with large numbers of culture forms by intraperitoneal route, and trypomastigotes appeared in their blood 3-8 days post-inoculation. One single epimastigote was also found in Mus musculus. Similar attempts to infect Rattus norvegicus, hamsters (Mesocricetus auratus), the opossum Didelphis marsupialis, the anteater Tamandua tetradactyla and triatomine bugs were unsuccessful, following six months of observations and microscopic examinations of blood films and blood cultures. As we have found no previous record of a Trypanosoma (Megatrypanum) species naturally infecting a member of the family Echimyidae, or any other caviomorph rodent, we conclude that this is the first time such an infection has been reported. The new species is unusual in the subgenus for its infectivity to laboratory mice.
authors.affiliation: Coordenação Sociedade, Ambiente e Saúde, Instituto Nacional de Pesquisas da Amazônia - INPA, Av. André Araújo, 2.936, Petrópolis, CEP 69011-970, Caixa Postal 478, Manaus, AM, Brasil.
authors.forename: Roberto Daibes
authors.initials: RD
authors.lastname: Naiff
authors.forename: Toby Vincent
authors.initials: TV
authors.lastname: Barrett
mesh_terms: D000818:Animals; D001938:Brazil; D006224:Cricetinae; D048293:Didelphis; D007303:Insect Vectors / Q000469:parasitology; D008297:Male; D051379:Mice; D051381:Rats; D012239:Rhodnius / Q000469:parasitology; D012376:Rodent Diseases / Q000469:parasitology*; D012377:Rodentia; D014345:Trypanosoma / Q000302:isolation & purification*; D014352:Trypanosomiasis / Q000469:parasitology / Q000662:veterinary*; D004490:Xenarthra