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Detection of DNA of Borrelia burgdorferi sensu lato was performed by PCR in taiga ticks Ixodes persulcatus, in blood samples and skin bioptates of small forest mammals, and in blood and urine samples of humans after attaching of ticks events. In Novosibirsk region both in natural reservoir and in patients with Ixodes ticks-borne borreliosis DNA of Borrelia garinii and Borrelia afzelii are detected. DNA of these borrelia were detected in 8 from 72 of taiga ticks, in 36 from 298 of blood and skin samples of small forest mammals, and in 32 from 102 of human blood and urine samples. In all studied samples DNA of B. garinii from NT29 subgroup was predominated. Borrelia DNA in which sequence of intergenic spacer region was homologous to sequence Chy13p first detected in China has been detected in one blood sample from red-backed vole (Clethrionomys rutilus).

The prevalence of Borrelia burgdorferi sensu lato (s.l.) genospecies in West Siberia as well as in many other regions of Russia remains insufficiently investigated. In the present study a total of 151 adult female ticks Ixodes persulcatus Schulze, collected at three localities in eastern regions of West Siberia, where Lyme disease is endemic, were examined for the presence of the spirochete B. burgdorferi s.l. by polymerase chain reaction targeting the 23S-5S rRNA intergenic spacer regions. Spirochetal DNA was detected in on average 15.2+/-3.0% of the ticks examined. The infection rate of adult ticks with B. burgdorferi s.l. at various localities ranged from 8.6+/-3.4% to 29.0+/-7.6%, being greatest in the northernmost site studied and decreasing southwards. The restriction patterns obtained after MseI digestion of the 23S-5S rRNA intergenic spacer amplicons assigned 23 DNA samples to the following genomic groups: 19 to B. garinii (12 to group NT29 and seven to group 20047(T)), three to B. afzelii, and one to mixed B. afzelii and B. garinii NT29. We have not detected other genospecies, which were found in ticks in Europe, the Russian Far East and Japan. Thus, the ticks examined were associated only with two genospecies of Borrelia burgdorferi s.l. pathogenic to humans (B. garinii and B. afzelii), and B. garinii was the major genospecies infecting adult I. persulcatus in eastern regions of West Siberia.

Borrelia burgdorferi sensu lato infecting Ixodes persulcatus ticks near Novosibirsk, Russia were detected using PCR with primers specific to 5S and 23S rRNA genes. Two genospecies, B. afzelii and B. garinii, were identified by the PCR-based restriction fragment length polymorphism analysis with Tru9-I restriction endonuclease. Comparison of the corresponding nucleotide sequences revealed considerable diversity of the 5S-23S intergenic spacer structure among B. garinii.