title: Detection and differentiation of Borrelia burgdorferi sensu lato in ticks collected from sheep and cattle in China.
abstract: BACKGROUND
  Lyme disease caused by Borrelia burgdorferi sensu lato complex is an important endemic zoonosis whose distribution is closely related to the main ixodid tick vectors. In China, isolated cases of Lyme disease infection of humans have been reported in 29 provinces. Ticks, especially ixodid ticks are abundant and a wide arrange of Borrelia natural reservoirs are present. In this study, we developed a reverse line blot (RLB) to identify Borrelia spp. in ticks collected from sheep and cattle in 7 Provinces covering the main extensive livestock regions in China.
  
  
  RESULTS
  Four species-specific RLB oligonucleotide probes were deduced from the spacer region between the 5S-23S rRNA gene, along with an oligonucleotide probe which was common to all. The species specific probes were shown to discriminate between four genomic groups of B. burgdorferi sensu lato i.e. B. burgdorferi sensu stricto, B. garinii, B. afzelii, and B. valaisiana, and to bind only to their respective target sequences, with no cross reaction to non target DNA. Furthermore, the RLB could detect between 0.1 pg and 1 pg of Borrelia DNA.A total of 723 tick samples (Haemaphysalis, Boophilus, Rhipicephalus and Dermacentor) from sheep and cattle were examined with RLB, and a subset of 667 corresponding samples were examined with PCR as a comparison. The overall infection rate detected with RLB was higher than that of the PCR test.The infection rate of B. burgdoreri sensu stricto was 40% in south areas; while the B. garinii infection rate was 40% in north areas. The highest detection rates of B. afzelii and B. valaisiana were 28% and 22%, respectively. Mixed infections were also found in 7% of the ticks analyzed, mainly in the North. The proportion of B. garinii genotype in ticks was overall highest at 34% in the whole investigation area.
  
  
  CONCLUSIONS
  In this study, the RLB assay was used to detect B. burgdorferi sensu lato in ticks collected from sheep and cattle in China. The results showed that B. burdorferi senso stricto and B. afzelii were mainly distributed in the South; while B. garinii and B. valaisiana were dominant in the North. Borrelia spirochaetes were detected in Rhipicephalus spp for the first time. It is suggested that the Rhipicephalus spps might play a role in transmitting Borrelia spirochaetes.
authors.affiliation: State Key Laboratory of Veterinary Etiological Biology, Key Laboratory ofVeterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China.
authors.forename: Qingli
authors.initials: Q
authors.lastname: Niu
authors.forename: Guiquan
authors.initials: G
authors.lastname: Guan
authors.forename: Jifei
authors.initials: J
authors.lastname: Yang
authors.forename: Yuguang
authors.initials: Y
authors.lastname: Fu
authors.forename: Zongke
authors.initials: Z
authors.lastname: Xu
authors.forename: Youquan
authors.initials: Y
authors.lastname: Li
authors.forename: Miling
authors.initials: M
authors.lastname: Ma
authors.forename: Zhijie
authors.initials: Z
authors.lastname: Liu
authors.forename: Junlong
authors.initials: J
authors.lastname: Liu
authors.forename: Aihong
authors.initials: A
authors.lastname: Liu
authors.forename: Qiaoyun
authors.initials: Q
authors.lastname: Ren
authors.forename: Wayne
authors.initials: W
authors.lastname: Jorgensen
authors.forename: Jianxun
authors.initials: J
authors.lastname: Luo
authors.forename: Hong
authors.initials: H
authors.lastname: Yin
mesh_terms: D000818:Animals; D015748:Borrelia burgdorferi Group / Q000235:genetics / Q000502:physiology*; D002417:Cattle / Q000382:microbiology* / Q000469:parasitology; D002681:China; D003870:Dermacentor / Q000382:microbiology; D006801:Humans; D015151:Immunoblotting / Q000662:veterinary; D026863:Ixodidae / Q000382:microbiology*; D008193:Lyme Disease / Q000382:microbiology / Q000635:transmission; D016133:Polymerase Chain Reaction / Q000662:veterinary; D012338:RNA, Ribosomal, 23S / Q000235:genetics; D012341:RNA, Ribosomal, 5S / Q000235:genetics; D048494:Rhipicephalus / Q000382:microbiology; D012756:Sheep / Q000382:microbiology* / Q000469:parasitology
chemical_list: D012338:RNA, Ribosomal, 23S; D012341:RNA, Ribosomal, 5S