Epidemiology and hematological analysis of dogs naturally infected by Hepatozoon spp. from central Brazil - retrospective study

Résumé

Hepatozoonosis is a hemoparasitosis caused by intracellular protozoa of the genus Hepatozoon, transmitted to dogs and other carnivores by parasitized ticks, such as Rhipicephalus sanguineus and Amblyomma spp. Its prevalence varies by geographic region, favoring tropical and subtropical areas. Hepatozoon spp. infection cause nonspecific clinical manifestation. This longitudinal retrospective study aims to highlight the epidemiological and hematological aspects of dogs naturally infected with Hepatozoon spp. in the municipality of Mineiros, state of Goiás, Brazil, between 2018–2022. This study considered the following information: age, sex, breed, distribution of cases over the years, seasonality, and hematological profile. A total of 272 domestic dogs were found to be parasitized by Hepatozoon spp. using the blood smear technique. Adult dogs were more likely to be affected by hepatozoonosis, with no breed or sexual predisposition. This study showed an exponential increase in cases diagnosed over the years, particularly in autumn and winter (the dry season). Within the study’s evaluation criteria, most dogs had anemia, thrombocytopenia, and hyperproteinemia; however, there were no changes in the total leukocyte count.