Multiple spacer sequence typing of carried by ticks in Gansu, China.

BACKGROUND

is a zoonotic pathogen that causes Q fever and is found worldwide. Ticks serve as the primary reservoir, playing an important role in maintaining the natural cycle of . is transmitted to animals when ticks feed on their blood. However, information on infection in ticks remains limited, despite the widespread prevalence of the infection in humans and animals across China.

METHODS

In this study, 192 engorged ticks were collected from Baiyin City of Gansu Province, China. The presence of in ticks was specifically identified by detecting the gene using nested polymerase chain reaction (nPCR). In addition, the 16S rRNA gene of was molecularly characterized using nPCR. A total of 10 spacer sequences (Cox 2, 5, 18, 20, 22, 37, 51, 56, 57, and 61) were amplified using PCR against positive specimens for MST analysis.

RESULTS

All collected ticks were identified as , and 90 of them tested positive for , with a positive rate of 46.9% (90/192). The 16S rRNA gene analysis showed that the novel variants detected in this study were closely related to other strains in the world. The allele codes found in the present study for loci Cox2-Cox5-Cox18-Cox20-Cox22-Cox37-Cox51-Cox56-Cox57-Cox61 were 8-4-9-5-7-5-2-3-11-6. This represents a novel combination of allele values, similar to MST28, currently designated as MST85 in the Multi Spacers Typing (MST) database.

CONCLUSION

Our results revealed the circulation of a novel MST genotype of in Baiyin City, Gansu Province, China. The detection of in ticks suggests a potential public health risk to the local human population.