Factors associated with epidemiology of Anaplasma platys in dogs in rural and urban areas of Minas Gerais State, Brazil.

This epidemiological survey of Anaplasma platys was carried out in rural and urban areas of three distinct regions of the State of Minas Gerais, Brazil. EDTA blood samples were collected during the dry season from dogs living on farms with an attempt to resample the same dogs in the subsequent rainy season. Samples were also taken from dogs in urban areas. DNA was extracted from blood samples for real time PCR. Risk factors, such as age, breed, sex, presence of ticks, and packed cell volume were analyzed. During the rainy season, the prevalence of infection by A. platys in dogs in the rural areas was significantly higher (13.9%) than that observed in dogs in the urban areas (5.1%). Dogs in the Nanuque region were 3.74 times (p=0.001) more likely to be real-time PCR positive than dogs in the other two studied regions. Dogs infested with ticks showed higher rates of positivity. The results showed that in rural areas of Minas Gerais A. platys infection is influenced by climatic conditions. In areas of higher temperature and higher humidity, transmission occurs during both the dry and rainy seasons, while in areas with lower temperature and humidity transmission occurs mainly during the dry season.