FML/QuilA-Vaccinated Dogs Naturally Infected with Leishmania infantum: Serum Cytokines, Clinicopathological Profile, and Parasitological Parameters.

Dogs are the main reservoir of Leishmania infantum in endemic regions. Canine leishmaniasis, caused by L. infantum, can progress to a chronic disease resulting in death. Vaccines have been developed with a certain degree of success. The pathogenesis of this disease is not completely understood, especially in previously vaccinated dogs. We herein described clinical data, parasite load, serum levels of cytokines, and the reservoir potential in vdogs vaccinated with the fucose-mannose ligand (FML)/QuilA saponin vaccine (Leishmune™) naturally infected (Vi) and compared to vaccinated not infected dogs (Vn). Thirty-four dogs from private owners were divided into two groups: vaccinated/infected and vaccinated/uninfected. Clinical evaluation, hematological and biochemical parameters, and serum levels of cytokines were measured by conventional methods. The parasite burden in the bone marrow was measured by quantitative real-time PCR, and the transmissibility of parasites to sand flies was assessed by xenodiagnosis. Clinical, biochemical, and hematological parameters of vaccinated infected dogs were mostly normal. Vi dogs developed mild disease with low clinical scores. Serum levels of IL-10 were higher in Vi dogs, and a strong correlation was observed in IL-4 levels and the A/G ratio in Vi dogs. These results suggest a role of TH2 response in Vi dogs, although more data is needed to better understand the disease in vaccinated dogs.

Antifeeding and short-term insecticidal effects against Lutzomya longipalpis in dogs treated with permethrin or deltamethrin / Efeitos não alimentação e inseticida em curto prazo sobre Lutzomyia longipalpis em cães tratados com permetrina ou deltametrina

Canine visceral leishmaniasis is a zoonotic disease caused by parasites of the genus Leishmania and transmitted by phlebotomine sandflies of the genus Lutzomyia in the New World and Phlebotomus in the Old World. The individual protection of dogs by treatment with permethrin 65% or by a 4% deltamethrin-impregnated collar is evaluated in this study based on the antifeeding of the products and the short term insecticidal antifeeding effects in the following sites on the dog's body: the inner side of the ear and the inguinal region. Both products produced a decrease in blood feeding and an increase in the antifeeding of the sandflies and the effects were not homogeneous, as there were significant differences between the effects on the pinna and on the inguinal region. The treatments of dogs with synthetic pyrethroids are important strategies to reduce the infection rates in endemic regions however the antifeeding and antifeeding effects were low and may not be sufficient to ensure a dog's individual protection.

Leishmaniose visceral canina é uma zoonose causada por parasitos do gênero Leishmania e transmitida por flebótomos do gênero Lutzomyia no Novo Mundo e Phlebotomus no Velho Mundo. A proteção individual do cão através do tratamento com produtos contendo permetrina 65% ou com a coleira impregnada com deltametrina 4% é avaliada no presente estudo, baseado nos efeitos de não alimetação e inseticida imediatos no pavilhão auditivo direito e região inguinal direita. Ambos os produtos demonstraram redução no ingurgitamento das fêmeas e aumento da mortalidade, mas o efeito não foi homogêneo, uma vez que foram verificadas diferenças estatisticamente significativas nos efeitos nas diferentes regiões. O tratamento dos cães com piretroides é uma importante estratégia para redução das taxas de infecção em regiões endêmicas, no entanto, os efeitos mortalidade e repelência foram baixos e podem não ser suficientes para a proteção individual do cão.