Circulação de Rickettsias do Grupo da Febre Maculosa em cães no entorno de Unidades de Conservação Federais do estado do Rio de Janeiro: evidência sorológica e fatores associados / Spotted Fever Group Rickettsiae in dogs at the surroundings of Conservation Units in the state of Rio de Janeiro: serological survey and associated factors

Doenças causadas por rickettsias tem ampla distribuição geográfica e estão associadas a artrópodes hematófagos. Rickettsia rickettsii é espécie mais patogênica do Grupo da Febre Maculosa (GFM) e responsável pela Febre Maculosa Brasileira. No sudeste do país a doença é endêmica e inquéritos sorológicos tem demonstrado presença de anticorpos para antígenos do GFM em cães, reforçando a participação do cão como sentinela. Os principais vetores são carrapatos do gênero Amblyomma, cujos hospedeiros são, muitas vezes, animais de vida silvestre. Assim, objetivou-se avaliar a circulação de rickettsias do GFM no entorno de Unidades de Conservação (UC) no Rio de Janeiro por meio da Imunofluorescência Indireta em cães, além de determinar os fatores associados. Amostras de soro de 155 cães foram testadas, sendo 16,1% dos animais sororreagentes pelo menos a um dos antígenos testados. Houve associação entre a sororreatividade dos cães e o acesso à mata; falta de assistência médico-veterinária; falta de medidas contra carrapatos; e renda familiar do responsável de até dois salários mínimos. Cães com este perfil apresentaram maior chance de serem expostos aos agentes do GFM. De acordo com o modelo de regressão logística, não frequentar áreas de mata foi considerado um fator de proteção para o cão, juntamente com possuir acompanhamento médico-veterinário e receber medidas contra carrapatos. Concluiu-se que patógenos do GFM circulam no entorno das UC estudadas, sendo possível que R. rickettsii e R. parkeri infectem cães, uma vez que os animais demonstraram exposição aos dois agentes. Ressalta-se a participação do veterinário e a adoção de medidas de combate a carrapatos como ferramentas na prevenção da infecção rickettsial.(AU)

Diseases caused by Rickettsiae have wide distribution and are associated with arthropods. Rickettsia rickettsii is the most pathogenic species of the Spotted Fever Group (SFG) and responsible for the Brazilian Spotted Fever. In the southeast the disease is endemic and serological surveys have demonstrated the presence of antibodies to SFG antigens in dogs, reinforcing the participation of the dog as sentinels. The main vectors are Amblyomma ticks, for which hosts are often wildlife animals. The aim of this study was to evaluate the presence of SFG Rickettsiae in the surroundings of Conservation Units (UC) at the state of Rio de Janeiro by Indirect Immunofluorescence Assay in dogs, and determine associated factors. Serum samples of 155 dogs were tested, with 16.1% of the seropositive animals at least to one of the antigens tested. There was an association between seroreactivity dogs and access to rainforest fragments; lack of veterinary care assistance; lack of actions against ticks; and family income up to two minimum salaries. Dogs with this profile had a higher chance of being exposed to SFG Rickettsiae. According to logistic regression, not going to rainforest areas was considered a protective factor for the dog along with the existence of veterinary care assistance and treatment against ticks. It was concluded that the SFG pathogens are present in the surroundings of UC studied, and possibly both R. rickettsii and R. parkeri are infecting dogs, since the animals showed exposure to both agents. We emphasize the participation of the veterinary and the adoption of the tick control measures as tools in preventing rickettsial infection.(AU)

[Development, survival and distribution of infective larvae of ruminants gastrointestinal nematodes, in the dry season of the "Fluminense lowland", State of Rio de Janeiro, Brazil]. / Desenvolvimento, sobrevivência e distribuição de larvas infectantes de nematóides gastrintestinais de ruminantes, na estação seca da Baixada Fluminense, RJ.

With the objective of studying the development, survival and the distribution of the infective larvae of gastrointestinal nematodes of domestic ruminant, in the period characterized as dry for the area of the Fluminense lowland, RJ, the artificial contamination of the pasture was accomplished with fecal samples of bovine, caprine and ovine, naturally infected. One week after, began the sampling of the faecal masses and of the grass around the same ones, with biweekly repetitions. Larvae of the genus Haemonchus and Trichostrongylus were recovered in the grass contaminated with bovine faeces still 21 weeks after deposit; in the contaminated samples with caprine faeces, the same genus were recovered still 15 weeks after contamination. In the ovine samples, the maximum survival was also of 15 weeks, when the genus Trichostrongylus was recovered. In the bovine, caprine and ovine faecal masses were still recovered larvae in the 21. 15 and 7 weeks after deposit, respectively. For evaluation of the distribution of the larvae in the pasture were studied their vertical and horizontal displacements. It was observed that the larvae migrated vertically, and that 90.6; 93.2 and 88.5% of the larvae of nematodes parasites of bovine, caprine and ovine respectively, were located in the superior half of the grass. It was observed that the horizontal displacement also happened, however, most of the infective larvae did not stand back more than 15 cm of the feces. The results indicate that even in conditions of low rainfalls, characteristic of the period, the environmental conditions made possible the development and the migration of the infective larvae.