Canine Visceral Leishmaniasis Case Investigation in the Jacare Region of Niteroi, Rio De Janeiro, Brazil

Abstract

SUMMARYAmerican visceral leishmaniasis is a vector-borne zoonosis in expansion in Brazil. Dogs are the main urban reservoir. Departing from a case of canine visceral leishmaniasis (CVL) in Jacaré, Niterói, Rio de Janeiro State, an epidemiological canine and entomological study was performed to assess the extension of the disease at the location. Sample was collected around the case and the dogs identified by serological tests (rapid double platform immunochromatographic exams, immunoenzymatic assay/ELISA, indirect immunofluorescence/IFAT). The parasitological diagnosis was performed in animals positive in at least one of these tests. The entomological study was carried out by using light traps and manual collection. The associations between canine variables and outcome (ELISA and IFAT reagents) were assessed by the chi-square test and adjusted by multivariate logistic regression for those associations with p < 0.1 in the bivariate analysis. Seventeen cases of CVL were detected among 110 evaluated dogs (prevalence of 15.5%). Presence of ectoparasites (OR 6.5; 95% CI 1.1-37.4), animals with clinical signs (OR 9.5; 95% CI 1.2-76.6), and previous cases of CVL in the same house (OR 17.9; 95% CI 2.2-147.1) were associated with the outcome. Lutzomyia longipalpiswas not detected. Our results are indicative of an ongoing transmission in the area.

Fatores ambientais associados à ocorrência de leishmaniose visceral canina em uma área de recente introdução da doença no Estado do Rio de Janeiro, Brasil

“…The entomological survey reported by Oliveira et al 16 , conducted in the same area and at the same time as this study, did not detect the principal vector of CVL transmission, Lu. longipalpis.…”

“…Even considering the inherent difficulties in the detection of leishmaniasis vectors, the finding suggests that other sand fly species found in this area, like Lu. migonei, may be involved in CVL transmission 16,33 .…”

“…New areas have been identified with the occurrence of canine visceral leishmaniasis (CVL) in various municipalities (counties) in the State of Rio de Janeiro 15,16,17 . However, little is known about the environmental factors involved in the emergence of CVL in these areas.…”

Serological tests fail to discriminate dogs with visceral leishmaniasis that transmit Leishmania infantum to the vector Lutzomyia longipalpis

“…Our results show that only ICrK39 and FAST could indicate infectiousness. RT-DPP and ELISA, which are used in the Brazilian VL control program 32 , were unable to discriminate the most infectious dogs. Negative DAT, FAST, and ICrK39 results can be used to distinguish some portion of the most infectious dogs, but a significant proportion of these animals will remain in the community.…”

Accidental and late parasitological diagnosis of Leishmania sp. in a dog from a low disease transmission area of Brazil: A case report

“…Despite the increase in the number of notified cases, Rio de Janeiro State is still considered a low transmission area (Brasil 2014). Despite living in the proximities of Serra da Tiririca, where the vector was found (Rodrigues et al 2013) and recent cases of the disease were described (Paula et al 2009, Oliveira et al 2015, the dog was from the Northeastern region of Brazil, where CanL is highly incident (Brasil 2014), and lived in this region for most of its life. Due to the slow evolution of the disease and the fact that the dog remained for a few days in the city of Niterói before the clinical symptoms appear, it is possible to determine that the infection occurred in Fortaleza.…”