Risk factors and clinical disorders of canine ehrlichiosis in the South of Bahia, Brazil

Abstract

ResumoObjetivou-se com este trabalho estudar as alterações clínicas, fatores de risco da ehrlichiose canina nos municípios de Ilhéus e Itabuna, Bahia, e comparar diferentes métodos de diagnóstico. Amostras de sangue foram coletadas de 200 cães e cada animal foi examinado clinicamente. Foi preenchido um questionário para avaliar os fatores de risco. As amostras de sangue foram analisadas pelo teste Dot-ELISA e foram realizadas hematimetria, contagem de plaquetas e procura de mórulas em esfregaço de sangue. Nested-PCR foi realizada em 50 amostras positivas e 50 negativas na sorologia. Três amostras PCRs positivas foram seqüenciadas. Foi encontrado 36,0% de positividade na sorologia e 5,5% nos esfregaços sanguíneos. Os animais apresentavam anemia e trombocitopenia. Ter carrapatos e residir em áreas suburbanas foram considerados fatores de risco (p < 0,05). A Nested-PCR identificou 11 cães positivos, sendo 9 com sorologia positiva e 2 negativos. O sequenciamento de DNA foi compatível com a presença de Ehrlichia canis.Palavras-chave: Ehrlichia canis, epidemiologia, ELISA, Nested PCR. AbstractThe aim of this work was to study the clinical disorders and risk factors of canine ehrlichiosis in Ilhéus and Itabuna, Bahia, and compare different diagnostic methods. Blood samples were collected from 200 dogs. Each dog was clinically examined. A questionnaire was used to evaluate the risk factors. The blood samples were analyzed using the Dot-ELISA test; hematometry, platelet counts and searches for morulae on blood smears were performed. Nested PCR was carried out on 50 serologically positive samples and 50 negative samples. Three positive PCRs were sequenced. Thirty-six percent were serologically positivity and 5.5% from blood smears. The animals were anemic and thrombocytopenic. Presence of ticks and living in areas on the urban periphery were considered to be risk factors (p < 0.05). Nested PCR identified 11 positive dogs of which nine were serologically positive and two were negative. The DNA sequencing was consistent with the presence of Ehrlichia canis.

Canine ehrlichiosis: prevalence and epidemiology in northeast Brazil

“…This value was higher than the 11% and 7.8% reported by Carlos et al (2011) andCarvalho et al (2008), respectively, who also conducted research in the southern region of Bahia. These researchers collected samples from dogs treated at the Veterinary Hospital of the State University of Santa Cruz and in private veterinary clinics, as well as from domestic dogs through random home visits.…”

“…Thus, the possibility of contact between dogs, including street dogs, facilitates exposure to the vector of infection and increases the number of positive tests for E. canis in this locality. In contrast, the animals studied by Carlos et al (2011) andCarvalho et al (2008) were domestic and had veterinary monitoring, which would have contributed to better animal health.…”

Occurrence of Ehrlichia canis and Anaplasma platys in household dogs from northern Parana

“…Therefore, it would be worth comparing the prevalence of these infectious agents in dogs with and without the characteristic clinical manifestations of CME and CTA. In this case, if prevalence levels are higher in dogs with clinical manifestations, the data should be interpreted as a consequence of the infectious agent and not as risk factors that might predispose the animal to infection (CARLOS et al, 2011). Alternatively, it is also possible to evaluate dogs that have reacted positively to one infectious agent by comparing the ratio of anemic and/or thrombocytopenic dogs with dogs having the globular volume and/or platelets scores within reference limits.…”

Ehrlichia canis detection in dogs from Várzea Grande: a comparative analysis of blood and bone marrow samples

“…Direct exposure to the vector tick, R. sanguineus (CARLOS et al, 2011) and age (COSTA JUNIOR et al, 2007) were considered risk factors for infection with E. canis in other regions; however, these factors were not associated with infection in the dogs surveyed, as described by SILVA et al (2012).…”