Leishmaniose visceral canina no Semiárido Paraibano.

Abstract

Leishmaniasis is a complex of infectious parasitic diseases caused by several protozoan species of the genus Leishmania. It has a zoonotic character and is therefore of great importance for public health. This thesis is composed of three chapters about visceral leishmaniasis in dogs and cats in Paraíba, Brazil. The first two are the results of the epidemiological study of canine visceral leishmaniasis (CVL) in the municipality of Santa Luzia, located in the Paraiba semiarid region. During blood collection, an epidemiological questionnaire was applied to the owners to identify the risk factors, and the geographic coordinates of the dogs' location were recorded for spatial distribution analysis. In 2015 and 2016, 779 dog blood samples were collected. The prevalence was determined by three serological techniques, considering positive the samples that reacted in at least two of them. The prevalence of anti-Leishmania infantum antibodies found in the municipality was 15% (117/779), being higher in urban area (15.2%) than in rural area (13.6%). The neighborhood with the highest prevalence was Frei Damião with 26.4% (33/125), being considered a risk factor (OR = 1.245), and where a high risk cluster was confirmed (RR = 2.48). Other risk factors found were semidomestic breeding (OR = 1.798) for dogs living in the urban area, and hunting (OR = 18.505), contact with cattle (OR = 17.298) and area where the dog is raised (OR = 4.802) for animals residing in rural areas. There is a high prevalence and wide and heterogeneously distribution of CVL in the city of Santa Luzia. The results suggest control and prevention measures should be prioritized based on identified risk factors in each areas in order to maximize the control program efficiency and minimize the chance of new canine and human cases. In the third chapter, the main epidemiological, clinical, pathological, serological and molecular aspects of the first report of L. infantum infection in cats in Paraíba State, Brazil, were described. The animals had multicenter, nodular and ulcerated skin lesions in the ears and muzzle and were submitted to clinical evaluation, followed by serological, molecular and parasitological exams, with culture and isolation of the parasite, that was characterized by isozyme electrophoresis. Case 1 was a female adult cat, a stray mongrel cat. Case 2 was a male adult cat, mongreland domiciled. Both were positive for the presence of anti-L. infantum antibodies. By fine needle aspiration cytology of cutaneous nodules and lymph nodes, amastigote forms of Leishmania spp. were found both free and inside macrophages. Histopathologically, the lesions were characterized by nodular and /or ulcerative granulomatous dermatitis associated with intralesional amastigote forms of Leishmania spp.. By Polymerase Chain Reaction, the L. infantum kDNA minicircle sequence was amplified. It was concluded that L. infantum infection occurs in cats in Paraíba State, Brazilian northeastern region. It is necessary to understand the immunological and epidemiological profile of visceral leishmaniasis in the feline population with a view to public health control measures.