贵阳市乌当区宠物中心犬体表寄生血红扇头蜱检出劳氏立克次体

Detection of Rickettsia raoultii in Rhipicephalus sanguineus parasitized on the body surfaces of dogs in pet centers in Wudang district,Guizhou,China

目的通过分子生物学技术检测蜱携带立克次体,了解宠物犬体表寄生蜱感染立克次体状况。方法2021年3-5月从贵阳市乌当区宠物中心宠物犬体表采集蜱样本,进行蜱种鉴定及蜱传立克次体柠檬酸合成酶基因(gltA)和外膜蛋白A基因(ompA)的PCR检测及基因型分析。结果从宠物犬体表采获蜱133只,通过形态学和蜱16S rRNA扩增,证实均为血红扇头蜱。通过立克次体特异ompA基因扩增、序列测定和遗传进化分析,证实蜱携带病原体为劳氏立克次体(Rickettsia raoultii)。结论发现宠物犬体表寄生血红扇头蜱,蜱存在劳氏立克次体感染,提示存在立克次体通过宠物犬寄生蜱感染人的风险,建议当地疾控机构对宠物蜱传立克次体的致病性及公共卫生风险做进一步评估。

Objective To investigate the Rickettsia infection and species of pet-dog-parasitizing ticks by the molecular biological technique.Methods Tick samples were collected from the body surfaces of pet dogs in pet centers in Wudang district,Guiyang,China from March to May 2021.Tick species identification and the polymerase chain reaction detection and genotyping of citrate synthase gene(gltA)and outer membrane protein A gene(ompA)of tick-borne Rickettsia were performed.Results A total of 133 ticks were collected from the body surfaces of pet dogs.The morphological characteristics and tick 16S rRNA amplification confirmed that all collected ticks were Rhipicephalus sanguineus.Rickettsia-specific ompA gene amplification,sequencing,and phylogenetic analysis confirmed that R.sanguineus were infected with R.raoultii.Conclusion R.sanguineus is found to parasitize the body surfaces of pet dogs and be infected with R.raoultii,indicating a risk of Rickettsia infecting humans through pet-dog-parasitizing ticks.It is recommended for the local health authorities to make further assessment of the pathogenicity and public health risks of pet-dog-parasitized tick-borne Rickettsia.