Molecular surveillance reveals a potential hotspot of tick-borne disease in Yakeshi City, Inner Mongolia

Abstract

A molecular surveillance of tick-borne diseases was performed in Hulunbuir City, Inner Mongolia. A total of 149 ticks including three species (Ixodes persulcatus, Haemaphysalis concinna, and Dermacentor silvarum) were collected. As many as 11 tick-borne bacterial pathogens were identified in them. Some of them have high positive rates. For example, Candidatus Rickettsia tarasevichiae was detected with a high prevalence of 72.48%, while Candidatus Lariskella sp. was detected in 31.54% of ticks. For both Rickettsia raoultii and Anaplasma phagocytophilum, two distinct genotypes were identified based on their phylogenetic trees based on 16S rRNA, gltA, and groEL sequences. Remarkable genetic diversity was also observed for 16S and flaB genes of Borreliella garinii, an agent of Lyme disease. Rickettsia heilongjiangensis causing Far-Eastern spotted fever (2.68%, 4/149), Ehrlichia muris causing human ehrlichiosis (4.70%, 7/149), Borrelia miyamotoi causing relapsing fever (2.01%, 3/149), and Borreliella afzelii causing Lyme disease (2.01%, 3/149) were also detected. Additionally, a previously uncharacterized Anaplasma species closely related to Anaplasma ovis was identified. Herein we name it “Candidatus Anaplasma mongolica”. Based on these results, we propose that Yakeshi City might be a potential hotspot of tick-borne diseases.

Tick-borne bacterial agents in Hyalomma asiaticum ticks from Xinjiang Uygur Autonomous Region, Northwest China

“…Rickettsia and Anaplasmataceae bacteria (mainly Anaplasma and Ehrlichia ) were detected by hemi-nested or nested PCR targeting a partial region of the 16S rRNA gene (approximately 900 bp for Rickettsia and 500 bp for Anaplasmataceae bacteria) [ 11 ]. After sequencing and alignment by BLASTn, the bacterial species were initially determined.…”

“…After sequencing and alignment by BLASTn, the bacterial species were initially determined. For further characterization, the gltA (citrate synthase) and groEL (60 kDa chaperonin) sequences were recovered from samples positive for Rickettsia , Ehrlichia , and Anaplasma using degenerate primers (primers shown in [ 11 ]) or specific primers (primers shown in [ 12 ]). The ompA sequences were additionally obtained from Rickettsia strains, while longer 16S sequences (approximately 800 bp) were obtained from Anaplasma strains [ 11 ].…”