Molecular Detection and Phylogenetic Characterization of Anaplasma spp. in Dogs from Hainan Province/Island, China

SIMPLE SUMMARY: Anaplasma is a Gram-negative parasitic bacterium transmitted by ticks. It has become an important tick-borne pathogen that endangers human and animal health in recent years. Dogs exposed to ticks are more likely to test positive for Anaplasma infection. This study confirms that dogs in Hainan province/island, China, are exposed to Anaplasma and raises the possibility that people and other animals could contract the disease. ABSTRACT: Anaplasmosis is a serious infection which is transmitted by ticks and mosquitos. There are very few reports and studies that have been carried out to understand the prevalence, distribution, and epidemiological profile of Anaplasma spp. infection in dogs in Hainan province/island. In the present study, we have tried to understand the prevalence, distribution, and occurrence of Anaplasma spp. infections in dogs (n = 1051) in Hainan Island/Province to establish a surveillance-based study. The confirmed positive samples by Polymerase chain reaction (PCR) were subjected to capillary sequencing for further strain-specific confirmation, followed by the construction of phylogenetic trees to determine their genetic relations. Various statistical tools were used to analyze related risk factors. There were three species of Anaplasma detected from the Hainan region; namely, A. phagocytophilum, A. bovis, and A. platys. The overall prevalence of Anaplasma is 9.7% (102/1051). A. phagocytopihum was prevalent in 1.0% of dogs (11/1051), A. bovis was found in 2.7% of dogs (28/1051), and A. platys in 6.0% of dogs (63/1051). Our surveillance-based study conducted to understand the occurrence and distribution pattern of Anaplasma spp. in Hainan will help in designing effective control measures along with management strategies so as to treat and control the infection in the area.