Anaplasma Phagocytophilum, a Zoonotic Vector-Borne Bacterial Species in Rodents and Its Associated Tick Vector: Systematic Review.

BACKGROUND

The bacterium Anaplasma phagocytophilum, the causative agent of tick-borne fever, is alleged to be naturally maintained in a tick-rodent cycle, with human beings involved only as incidental impasse hosts. This study was undertaken to update scientific evidence on the occurrence of A. phagocyphilum in rodents and its associated tick species.

RESULTS

The systematic review was executed using the PRISMA guidelines to assess and compile the relevant literature. Published journal articles from 1 January 2000 to August 2023 were sourced from three electronic databases, including PubMed, ScienceDirect and Google Scholar, and after evaluation of the articles, ultimately 23 were eligible for this systematic review. Of the eligible studies, 43.5% did not report on the detection of A. phagocytophilum in tick species but only in rodents, whilst 26.1% of the studies, reported on negative detection of A. phagocytophilum in both rodents and ticks. In terms of rodents, there were 11 genera observed from the eligible studies with Apodemus spp. being the most frequently reported host, followed by Microtus spp. and Myodes spp. Ixodes ticks including I. ricinus and I. trianguliceps were the most frequent tick species investigated as arthropod carriers/vectors in the studies, followed by Dermacentor and Haemaphysalis tick species.

CONCLUSIONS

This study has consolidated information from published articles on the role that rodents play as hosts or carriers of A. phagocytophilum and the possible role that related tick species play as vectors. Various tick species play a significant role as vectors of Anaplasma phagocytophilum and infect a wide array of rodent hosts that may possibly interact with humans.