This study identified the types and pathogen carrying status of fleas on the surface of sheep in some areas of southern Xinjiang,and analyzed the genetic evolution differences with respect to related pathogens.The aim was to provide a reference for the local prevention and control of fleas and insect borne infectious diseases.A total of 1 586 fleas were collected from agricultural and pas-toral areas of Tumushuke City and Hotan Prefecture.Flea species were identified on the basis of morphology and the Pulex irritans mi-tochondrial COII gene.Flea DNA was extracted,and PCR was conducted to amplify the Bartonella gltA gene;Arsenophonus,Ana-plasma,Ehrlichia,and Wolbachia 16S rRNA genes;RickettsiaOmpA,17kDa,16S rRNA genes,and Yersinia pestis 16S rDNA gene.The amplified products were sequenced,and the homology of the genes of the three detected pathogens(gltA gene of Bartonella,16S rRNA gene of Wolbachia,and Anaplasma phagocytophilum)with respect to known corresponding genes of the same pathogen in Gen-Bank was analyzed.Phylogenetic trees were constructed with the adjacency method in MEGA 11.0.According to morphological and mo-lecular biology identification results,all fleas collected in this study were Pulex irritans.PCR indicated that the target gene fragments had been added to the mitochondrial COII,BartonellagltA,Wolbachia,and autophagosomal 16S rRNA genes of human fleas,all of which were consistent with the expected fragment sizes.Target bands were not amplified from Ehrlichia,Arsenophonus,spotted fever group Rickettsia,and Yersinia pestis.According to homology and genetic evolution analysis of human flea mitochondrial COII and the corresponding genes of the above-described pathogens,the COX2 gene(ON455234.1)of human fleas in Tumushuke city and Iran ob-tained in this study showed the highest homology(99.84%).The COII gene(NC_063709.1)of human fleas in Hetan City and Hunan region showed the highest homology(100%).Our findings further confirmed that the flea species was Pulex irritans.The PCR amplifi-cation results indicated that the collected Pulex irritans carried multiple pathogens,among which Bartonella and Wolbachia had the highest infection rates,and the infection rate with Anaplasma phagocytophilum was relatively low.This study is the first to discover flea species on the surface of sheep in some areas of southern Xinjiang.Our findings preliminarily confirmed that Bartonella,Wolba-chia,and Anaplasma phagocytophilum are the main Pulex irritans pathogens.

This study identified the types and pathogen carrying status of fleas on the surface of sheep in some areas of southern Xinjiang,and analyzed the genetic evolution differences with respect to related pathogens.The aim was to provide a reference for the local prevention and control of fleas and insect borne infectious diseases.A total of 1 586 fleas were collected from agricultural and pas-toral areas of Tumushuke City and Hotan Prefecture.Flea species were identified on the basis of morphology and the Pulex irritans mi-tochondrial COII gene.Flea DNA was extracted,and PCR was conducted to amplify the Bartonella gltA gene;Arsenophonus,Ana-plasma,Ehrlichia,and Wolbachia 16S rRNA genes;RickettsiaOmpA,17kDa,16S rRNA genes,and Yersinia pestis 16S rDNA gene.The amplified products were sequenced,and the homology of the genes of the three detected pathogens(gltA gene of Bartonella,16S rRNA gene of Wolbachia,and Anaplasma phagocytophilum)with respect to known corresponding genes of the same pathogen in Gen-Bank was analyzed.Phylogenetic trees were constructed with the adjacency method in MEGA 11.0.According to morphological and mo-lecular biology identification results,all fleas collected in this study were Pulex irritans.PCR indicated that the target gene fragments had been added to the mitochondrial COII,BartonellagltA,Wolbachia,and autophagosomal 16S rRNA genes of human fleas,all of which were consistent with the expected fragment sizes.Target bands were not amplified from Ehrlichia,Arsenophonus,spotted fever group Rickettsia,and Yersinia pestis.According to homology and genetic evolution analysis of human flea mitochondrial COII and the corresponding genes of the above-described pathogens,the COX2 gene(ON455234.1)of human fleas in Tumushuke city and Iran ob-tained in this study showed the highest homology(99.84%).The COII gene(NC_063709.1)of human fleas in Hetan City and Hunan region showed the highest homology(100%).Our findings further confirmed that the flea species was Pulex irritans.The PCR amplifi-cation results indicated that the collected Pulex irritans carried multiple pathogens,among which Bartonella and Wolbachia had the highest infection rates,and the infection rate with Anaplasma phagocytophilum was relatively low.This study is the first to discover flea species on the surface of sheep in some areas of southern Xinjiang.Our findings preliminarily confirmed that Bartonella,Wolba-chia,and Anaplasma phagocytophilum are the main Pulex irritans pathogens.