Detection of Ehrlichia canis in domestic cats in the central-western region of Brazil

Ehrlichiosis is a worldwide distributed disease caused by different bacteria of the Ehrlichia genus that are transmitted by arthropod vectors. Its occurrence in dogs is considered endemic in several regions of Brazil. Regarding cats, however, few studies have been done and, consequently, there is not enough data available. In order to detect Ehrlichia spp. in cats from the central-western region of Brazil, blood and serum samples were collected from a regional population of 212 individuals originated from the cities of Cuiabá and Várzea Grande. These animals were tested by the Immunofluorescence Assay (IFA) and the Polymerase Chain Reaction (PCR) designed to amplify a 409 bp fragment of the dsb gene. The results obtained show that 88 (41.5%) cats were seropositive by IFA and 20 (9.4%) cats were positive by PCR. The partial DNA sequence obtained from PCR products yielded twenty samples that were found to match perfectly the Ehrlichia canis sequences deposited on GenBank. The natural transmission of Ehrlichia in cats has not been fully established. Furthermore, tick infestation was not observed in the evaluated cats and was not observed any association between age, gender and positivity of cats in both tests. The present study reports the first serological and molecular detection of E. canis in domestic cats located in the endemic area previously mentioned.

Phlebotomine sand flies and canine infection in areas of human visceral leishmaniasis, Cuiabá, Mato Grosso / Flebotomíneos e infecção canina em áreas de leishmaniose visceral humana, Cuiabá, Mato Grosso

Visceral leishmaniasis is a systemic infectious disease that can cause to a severe, potentially life-threatening chronic condition in humans. Risk factors for infection in urban areas have been associated with poor living conditions, the presence of sand fly vectors and infected pets. This study aimed to describe sand fly and canine infection in the neighborhoods of human visceral leishmaniasis occurrence in the city of Cuiabá, Mato Grosso State, central-western Brazil, reported between January 2005 and December 2006. A total of 1,909 sand flies were collected. They were predominantly males and the most frequent species were Lutzomyia cruzi (81.25 percent), Lutzomyia whitmani (13.88 percent) and Lutzomyia longipalpis (2.62 percent). The sand fly density was not significantly correlated with the variation of environmental factors. The prevalence of canine visceral leishmaniasis in the neighborhoods studied was 26.82 percent and it was found that areas with high density of vectors coincided with areas of high prevalence of dogs and those with the highest rates of human cases. The study of vectors and other potential hosts are essential for a good understanding of visceral leishmaniasis and the related public health concerns, aiming at the prevention and control of leishmaniasis in the city of Cuiabá, Mato Grosso State.

A leishmaniose visceral é uma doença infecciosa sistêmica, de evolução crônica grave, potencialmente fatal para o homem. Os fatores de risco para a infecção em áreas urbanas têm sido associados às precárias condições de moradia, à presença de flebotomíneos vetores e de animais domésticos infectados. O presente trabalho objetivou descrever a fauna flebotomínica e infecção canina nos bairros de ocorrência da leishmaniose visceral humana no município de Cuiabá, Mato Grosso, notificados no período de janeiro de 2005 a dezembro de 2006. Foram coletados 1.909 flebotomíneos, as espécies mais frequentes foram Lutzomyia cruzi (81,25 por cento), Lutzomyia whitmani (13,88 por cento) e Lutzomyia longipalpis (2,62 por cento). A densidade de flebotomíneos não apresentou correlação significativa com a variação dos fatores ambientais. A prevalência de leishmaniose visceral canina nos bairros foi de 26,82 por cento e observou-se que as regiões com grande densidade de vetores coincidem com áreas de alta prevalência em cães e áreas nas quais foi detectado o maior número de casos humanos. O estudo de vetores e outros possíveis hospedeiros são imprescindíveis para um bom entendimento da doença a fim de gerar benefícios para a saúde pública, visando à prevenção e o controle das leishmanioses no município de Cuiabá e no Estado de Mato Grosso.

A expansão da epidemia da leishmaniose visceral no Estado de Mato Grosso, 1998-2005 / The spread of the visceral leishmaniasis epidemic in the State of Mato Grosso, 1998-2005

Uma epidemia de leishmaniose visceral teve início em 1998 na Região Metropolitana de Cuiabá, capital de Mato Grosso, atingindo hoje 34 (24,1 por cento) dos 141 municípios do estado. Entre janeiro de 1998 e dezembro de 2005, foram notificados 138 casos autóctones, predominando o sexo masculino (58 por cento), crianças (51,5 por cento) de 0-9 anos e residentes (66,7 por cento) de áreas urbanas. A leishmaniose visceral canina foi identificada em 41 municípios, com soropositividade de 9 por cento em 40.000 cães examinados. Lutzomyia longipalpis e/ou Lutzomyia cruzi foram capturadas em 14 dos 18 municípios que registraram simultaneamente leishmaniose visceral humana e canina. Os resultados indicam que a transmissão da leishmaniose visceral dissemina-se para o interior do estado, acompanhando o fluxo migratório e o processo de ocupação urbana desordenada das cidades. A presença isolada de Lutzomyia cruzi em municípios com alta incidência de casos humanos e caninos de leishmaniose visceral sugere possível participação desta espécie na cadeia de transmissão dessa parasitose em Mato Grosso.

An epidemic of visceral leishmaniasis began in 1998, in the Metropolitan Region of Cuiabá, the capital of the State of Mato Grosso, Brazil. Today, it has reached 34 (24.1 percent) of the 141 municipalities in the state. Between January 1998 and December 2005, 138 autochthonous cases were notified, mainly in males (58 percent), children aged 0-9 years (51.5 percent) and inhabitants of urban areas (66.7 percent). Canine visceral leishmaniasis has been detected in 41 municipalities, with positive serum in 9 percent of the 40,000 dogs examined. Lutzomyia longipalpis and/or Lutzomyia cruzi were captured in 14 out of the 18 municipalities that simultaneously recorded both human and canine visceral leishmaniasis. These findings indicate that visceral leishmaniasis transmission has become disseminated throughout the state, following migratory flows and the process of disorderly occupation of urban areas. The presence of Lutzomyia cruzi alone in areas with high incidence of human and canine cases suggests possible participation by this species in the transmission chain for visceral leishmaniasis in Mato Grosso.