Great genetic diversity of vector-borne bacteria and protozoan in wild rodents from Guangxi, China

PLoS Negl Trop Dis. 2024 May 13;18(5):e0012159. doi: 10.1371/journal.pntd.0012159. eCollection 2024 May.

Abstract

Background: Rodents are recognized as the hosts of many vector-borne bacteria and protozoan parasites and play an important role in their transmission and maintenance. Intensive studies have focused on their infections in vectors, especially in ticks, however, vector-borne bacterial and protozoan infections in rodents are poorly understood although human cases presenting with fever may due to their infection have been found.

Methods: From May to October 2019, 192 wild rodents were trapped in wild environment of Guangxi Province, and the spleen samples were collected to reveal the presence of vector-borne bacterial and protozoan infections in them. The microorganisms in rodents were identified by detecting their DNA using (semi-)nested PCR. All the PCR products of the expected size were subjected to sequencing, and then analyzed by BLASTn. Furthermore, all the recovered sequences were subjected to nucleotide identity and phylogenetic analyses.

Results: As a result, 192 rodents representing seven species were captured, and Bandicota indica were the dominant species, followed by Rattus andamanensis. Based on the (semi-)nested PCR, our results suggested that Anaplasma bovis, Anaplasma capra, Anaplasma ovis, Anaplasma phagocytophilum, "Candidatus Neoehrlichia mikurensis", "Candidatus E. hainanensis", "Candidatus E. zunyiensis", three uncultured Ehrlichia spp., Bartonella coopersplainsensis, Bartonella tribocorum, Bartonella rattimassiliensis, Bartonella silvatica, two uncultured Bartonella spp., Babesia microti and diverse Hepatozoon were identified in six rodent species. More importantly, six species (including two Anaplasma, two Bartonella, "Ca. N. mikurensis" and Bab. microti) are zoonotic pathogens except Anaplasma bovis and Anaplasma ovis with zoonotic potential. Furthermore, dual infection was observed between different microorganisms, and the most common type of co-infection is between "Ca. N. mikurensis" and other microorganisms. Additionally, potential novel Bartonella species and Hepatozoon species demonstrated the presence of more diverse rodent-associated Bartonella and Hepatozoon.

Conclusions: The results in this work indicated great genetic diversity of vector-borne infections in wild rodents, and highlighted the potential risk of human pathogens transmitted from rodents to humans through vectors.

MeSH terms

  • Anaplasma / classification
  • Anaplasma / genetics
  • Anaplasma / isolation & purification
  • Animals
  • Animals, Wild / microbiology
  • Animals, Wild / parasitology
  • Bacteria / classification
  • Bacteria / genetics
  • Bacteria / isolation & purification
  • Bartonella / classification
  • Bartonella / genetics
  • Bartonella / isolation & purification
  • China / epidemiology
  • Genetic Variation*
  • Phylogeny
  • Rats
  • Rodentia* / microbiology
  • Rodentia* / parasitology
  • Vector Borne Diseases / epidemiology
  • Vector Borne Diseases / microbiology
  • Vector Borne Diseases / parasitology
  • Vector Borne Diseases / transmission

Grants and funding

This study was supported by the National Key Research and Development Program (2021YFC2301202 to KL); by the Hebei Natural Science Foundation (No. C2022406003 to WPG); by the Young Talent Program of Higher School in Hebei Province (No. BJ2020024 to WPG); and by the Scientific Research Foundation for High-level Talents of Chengde Medical University (No. 202001 to WPG). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.