Human-pathogenic Anaplasma spp., and Rickettsia spp. in animals in Xi'an, China

Wen-Ping Guo1,2, Baicheng Huang1,2, Qin Zhao1,2

  • 1Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China.

Insights

Tick-borne bacteria pose a public health risk in Xi'an, China. Researchers found a high prevalence of Anaplasma capra and two novel Anaplasma species in domestic animals and ticks, highlighting the need for further investigation.

Area of Science:

  • Veterinary Microbiology
  • Public Health
  • Tick-borne Diseases

Background:

  • Thirteen tick-borne rickettsiales bacteria pathogenic to humans have been identified in China.
  • Diseases resembling human rickettsial infections have been observed in Xi'an, but the causative agents remain uninvestigated.
  • Tick-borne rickettsiales pose a significant threat to both animal and human health.

Purpose of the Study:

  • To investigate the prevalence of tick-borne rickettsiales bacteria pathogenic to humans in Xi'an, China.
  • To identify novel Anaplasma species and assess their genetic diversity.
  • To evaluate the public health risk associated with these pathogens in the region.

Main Methods:

  • Collection and testing of domestic animals and ticks from Xi'an, China.
  • Molecular detection of rickettsiales bacteria using PCR and sequencing.
  • Phylogenetic analysis of identified Anaplasma species based on rrs, groEL, and gltA genes.

Main Results:

  • A high prevalence of Anaplasma capra was detected, indicating a substantial public health risk.
  • Two novel Anaplasma species, closely related to Anaplasma phagocytophilum, were identified in goats.
  • Candidatus Rickettsia jingxinensis was detected in Haemaphysalis longicornis ticks with high prevalence.

Conclusions:

  • The study reveals a significant presence of tick-borne rickettsiales, including Anaplasma capra and novel Anaplasma species, in Xi'an.
  • The identified novel Anaplasma species circulating in goats require further pathogenicity assessment.
  • The findings underscore the urgent need for enhanced surveillance and control of tick-borne diseases in the region.

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