Molecular detection, risk factors, and phylogenetic analysis of tick-borne pathogens in dogs from northern Vietnam

In tropical regions, numerous tick-borne pathogens (TBPs) play a crucial role as causative agents of infectious diseases in humans and animals. Recently, the population of companion and pet dogs has significantly increased in Vietnam; however, information on the occurrence of TBPs is still limited. The objectives of this investigation were to determine the occurrence rate, risk factors, and phylogenetic characteristics of TBPs in dogs from northern Vietnam. Of 341 blood samples tested by PCR, the total infection of TBPs was 73.9% (252/341). Babesia vogeli (18SrRNA gene - 30.5%) was detected most frequently in studied dogs followed by Rickettsia spp. (OmpA gene - 27%), Anaplasma platys (groEL gene - 22%), Bartonella spp. (16SrRNA - 18.8%), Mycoplasma haemocanis (16SrRNA - 9.4%) and Hepatozoon canis (18SrRNA gene - 1.2%), respectively. All samples were negative for Ehrlichia canis and Anaplasma phagocytophylum. Co-infection was detected in 31.4% of the samples (107/341) of which, A. platys/Bartonella spp. (34/94,10%), Rickettsia spp./B. vogeli (19/94, 5.6%), and M. haemocanis/B. vogeli (19/94, 5.6%) were recorded as the three most frequent two species of co-infection types. Statistical analysis revealed a significant correlation between TBP infection and several host variables regarding age, breed, and living area in the current study. The recent findings reported herein, for the first time in Vietnam, are essential for local veterinarians when considering the appropriate approaches for diagnosing these diseases. Furthermore, this data can be used to establish control measures for future surveillance and prevention strategies against canine TBPs in Vietnam.