Field and experimental symptomless infections support wandering donkeys as healthy carriers of Trypanosoma vivax in the Brazilian Semiarid, a region of outbreaks of high mortality in cattle and sheep

Abstract\ud \ud Background\ud The Brazilian Semiarid is the home of the largest herd of donkeys in South America and of outbreaks of Trypanosoma vivax infection of high mortality in dairy cattle and sheep. For a comprehensive understanding of the underlying mechanisms of these outbreaks and epidemiological role of donkeys, we surveyed for T. vivax in wandering donkeys and follow the experimental infection of donkeys and sheep with a highly virulent isolate from the Semiarid.\ud \ud \ud Methods\ud Blood samples from 180 randomly selected wandering donkeys from the Brazilian Semiarid region were employed for PCV and parasitemia assessments and tested using the T. vivax-specific TviCATL-PCR assay. PCR-amplifed Cathepsin L (CATL) sequences were employed for genotyping and phylogenetic analysis. Four wandering donkeys were experimentally infected with a T. vivax isolate obtained during an outbreak of high mortality in the Semiarid; the control group consisted of two non-inoculated donkeys.\ud \ud \ud Results\ud We detected T. vivax in 30 of 180 wandering donkeys (16.6 %) using TviCATL-PCR. The prevalence was higher during the dry (15.5 %) than the wet season (1.1 %) and more females (23.1 %) than males (8.9 %) were infected. All the PCR-positive donkeys lacked patent parasitemia and showed normal values of body condition score (BCS) and packed cell volume (PCV). To evaluate the probable tolerance of donkeys to T. vivax, we inoculated five donkeys with a highly virulent isolate (TviBrRp) from the Semiarid. All inoculated donkeys became PCR-positive, but their parasitemia was always subpatent. A control goat inoculated with TviBrRp showed increasing parasitemia concurrently with fever, declining PCV, tachycardia, mucous membrane pallor, enlarged lymph nodes and anorexia. None of these signs were observed in donkeys. However, T. vivax from wandering donkeys shared identical or highly similar genotypes (identified by Cathepsin L sequences) with isolates from cattle and sheep outbreaks of acute disease in the Semiarid.\ud \ud \ud Conclusions\ud This is the first report of T. vivax in donkeys in Brazil and, to our knowledge, the first experimental infection of donkeys with T. vivax. The symptomless field and experimental infections corroborated that donkeys are more tolerant to T. vivax than other livestock species as shown in African countries. Therefore, farmers, veterinaries and control programmes should be aware of healthy carrier donkeys as a possible source of T. vivax for susceptible livestock species in the Brazilian Semiarid.CNPq and CAPES Brazilian agencies supported this research. CMFR is a PhD\ud fellow of CNPq and HAG and ACR are recipients of post-doctoral fellowships\ud from CNPq (PDJ) and CAPES (PNPD

II Consenso Brasileiro de Tuberculose: Diretrizes Brasileiras para Tuberculose 2004

Universidade Federal de São Paulo (UNIFESP) Escola Paulista de MedicinaUniversidade Federal do Rio de Janeiro Instituto Doenças do TóraxRede TB de PesquisaMinistério da Saúde Centro de Referência Hélio Fraga Laboratório Nacional de BacteriologiaUniversidade Federal da BahiaSociedade Brasileira de Cirurgia TorácicaUniversidade de São Paulo Faculdade de Medicina de Ribeirão PretoUniversidade Federal do Rio de Janeiro IPPMGSociedade Brasileira de PediatriaUniversidade Federal do Espírito Santo Faculdade de Medicina Núcleo de Doenças InfecciosasSecretaria de Estado da Saúde da Paraíba Coordenação de TuberculoseSecretaria de Estado da Saúde da Bahia Hospital Otávio MangabeiraSecretaria de Estado da Saúde de São Paulo Instituto Clemente FerreiraFundação Ataulpho de PaivaMinistério da Saúde Secretaria de Vigilância em Saúde Programa Nacional de DST/AidsUniversidade Estadual do Rio de Janeiro Hospital Universitário Pedro ErnestoMinistério da Saúde Centro de Referência Hélio FragaUniversidade Federal do Rio Grande do NorteUniversidade Federal da Bahia Instituto de Saúde ColetivaPontifícia Universidade CatólicaUniversidade Estadual do Rio de JaneiroMinistério da Saúde Secretaria de Vigilância à Saúde Coordenação Geral de Doenças EndêmicasUniversidade de São Paulo Faculdade de Medicina Hospital das ClínicasSociedade Brasileira de Pneumologia e Tisiologia Comissão de TuberculoseUniversidade de São Paulo Faculdade de Saúde PúblicaFIOCRUZ Escola Nacional de Saúde PúblicaSecretaria Municipal da Saúde Hospital Municipal Raphael de Paula SouzaUniversidade Federal do Pará Hospital Universitário João de Barros Barreto BelémSecretaria de Estado da Saúde Hospital Sanatório Parthenon de Porto AlegreUniversidade Federal do ParanáSociedade Brasileira de Pneumologia e Tisiologia Comissão de InfecçõesSecretaria da Saúde do Município do Rio de Janeiro Coordenação de TuberculoseUniversidade Federal de Minas Gerais Faculdade de MedicinaSecretaria de Estado da Saúde de São Paulo Centro de Vigilância Epidemiológica Coordenação de TuberculoseSecretaria de Estado da Saúde de São Paulo Centro de Referência DST/AidsUniversidade de São Paulo Faculdade de MedicinaUNIFESP, EPMSciEL