Epidemiological aspects and spatial distribution of human and canine visceral leishmaniasis in an endemic area in northeastern Brazil.

Visceral leishmaniasis (VL) is a systemic disease endemic in tropical countries and transmitted through sand flies. In particular, Canis familiaris (or domesticated dogs) are believed to be a major urban reservoir for the parasite causing the disease Leishmania. The average number of human VL cases was 58 per year in the state of Sergipe. The city of Aracaju, capital of Sergipe in Northeastern Brazil, had 159 cases of VL in humans. Correlatively, the percentage of serologically positive dogs for leishmaniasis increased from 4.73% in 2008 to 12.69% in 2014. Thus, these studies aimed to delineate the spatial distribution and epidemiological aspects of human and canine VL as mutually supportive for increased incidence. The number of human cases of VL and the frequency of canine positive serology for VL both increased between 2008 and 2014. Spatial distribution analyses mapped areas of the city with the highest concentration of human and canine VL cases. The neighbourhoods that showed the highest disease frequency were located on the outskirts of the city and in urbanised areas or subjected to development. Exponential increase in VL-positive dogs further suggests that the disease is expanding in urban areas, where it can serve as a reservoir for transmission of dogs to humans via the sand fly vector.

Differential protein abundance in promastigotes of nitric oxide-sensitive and resistant Leishmania chagasi strains.

PURPOSE: Leishmania chagasi is the causative agent of zoonotic visceral leishmaniasis in Brazil. Domestic and stray dogs are the main reservoirs. The life cycle of the parasite involves two stages. Promastigotes are extracellular and develop within the sand fly gut. Amastigotes survive inside the harsh environment of the phagolysosome of mammalian host phagocytes, which display the nitric oxide defense mechanism. Surprisingly, we were able to isolate promastigotes that are also resistant to NO. This finding may be explained by the preadaptative hypothesis. An insight into the proteome of NO-sensitive and resistant promastigotes is presented herein. EXPERIMENTAL DESIGN: Total protein extracts were prepared from promastigote cultures of an NO-sensitive and a resistant strain at early-logarithmic, mid-logarithmic and stationary phase. A population enriched in metacyclic promastigotes was also isolated by Percoll gradient centrifugation. In vitro infectivity of both strains was compared. Differential protein abundance was analyzed by 2DE-MALDI-TOF/TOF. The most striking results were tested at the mRNA level by qRT-PCR. Three biological replicates were performed in all cases. RESULTS: NO-resistant L. chagasi promastigotes are more infective than NO-sensitive ones. Among the differentially abundant spots, 40 proteins could be successfully identified in the sensitive strain and 38 in resistant promastigotes. CONCLUSIONS AND CLINICAL RELEVANCE: The increase of G6PD and the decrease of ARG and GPX transcripts and proteins contribute to NO resistance in L. chagasi promastigotes. These proteins may be studied as potential drug targets and/or vaccine candidates in the future.

In vitro infection by Leishmania infantum in the peripheral blood mononuclear cell-derived macrophages from crab-eating foxes (Cerdocyon thous).

Wild canids are natural reservoirs of visceral leishmaniais (VL). In Brazil, only the crab-eating fox (Cerdocyon thous) is a natural reservoir of this zoonotic disease, but there is still a lack of understanding regarding the sylvatic transmission of the Leishmania infantum infection. This is the first study on the isolation, cultivation and infection with L. infantum in the peripheral blood mononuclear cell-derived macrophages from crab-eating foxes. It is also the first to compare macrophages from crab-eating foxes to other canine macrophages under the same conditions. Blood samples collected from crab-eating foxes held at the local zoo were processed to obtain macrophages that were subsequently infected with stationary phase L. infantum promastigotes. The percentage of infected macrophages and intracellular amastigotes per 100 macrophages were similar in both fox and dog blood samples at 2h after infection. Unlike dog macrophages, in fox macrophages there was a significant reduction in the number of infected macrophages after 24 and 48 h. At 72 h after infection, the intracellular amastigotes were practically undetectable. These results indicate that crab-eating foxes have cellular mechanisms of infection control as efficient as the domestic dog. Further study is required to discern the potential epidemiologic role of crab-eating foxes in the visceral leishmaniasis transmission cycle.

Isolamento de estafilococos multirresistentes de otites em cães e sua importância para a saúde pública / Isolation of multiresistant staphylococci from canine otitis and its importance for public health

Foi pesquisada a ocorrência de Staphylococcus spp como agente causal de otite em cães da cidade de Aracaju, Sergipe. Cinqüenta e cinco amostras foram coletadas em clínicas particulares da cidade e analisadas para pesquisa de Staphylococcus sp. Foi utilizado o método tradicional e Staphylococcus foi isolado em 18 (32,7%) das 55 amostras coletadas. As espécies isoladas foram S. intermedius, S. aureus e S. schleiferi. Também foi realizada a prova de sensibilidade antimicrobiana pelo método de difusão em ágar. Esses patógenos oportunistas foram mais sensíveis à cefalexina, ao imipenem, à teicoplanina, à vancomicina e à amoxicilina/ácido clavulânico, sendo os antimicrobianos menos eficazes à clindamicina, azitromicina, neomicina e sulfa/trimetoprim. Pelo menos 83% dos isolados foram resistentes a um dos antimicrobianos. O isolamento de Staphylococcus resistente à oxacilina (17% dos isolados) é preocupante devido a sua implicação em saúde pública, mostrando que pequenos animais podem ser fonte potencial para o homem de patógenos resistentes a antimicrobianos.

Resistência antimicrobiana de Salmonella sp isolada de carne de frango resfriada comercializada em Aracaju, Sergipe / Antimicrobial resistance of Salmonella sp isolated from refrigerated poultry meat sold in Aracaju, Sergipe

Salmonella é um dos patógenos mais comumente relacionados com enfermidades transmitidas por alimentos em humanos, freqüentemente associada com o consumo de aves e seus derivados. Da mesma forma, a sua resistência a diversos tipos de antimicrobianos vem tornando-se um problema importante para a saúde pública. O objetivo deste estudo foi o de avaliar a contaminação de carcaças e vísceras de frangos resfriadas comercializadas em supermercados de Aracaju, SE, por Salmonella e verificar a sensibilidade deste patógeno a diferentes antimicrobianos. A presença de Salmonella Muenchen foi verificada em uma das amostras, tendo uma alta sensibilidade aos antimicrobianos testados.