First isolation of Borrelia lusitaniae DNA from Ixodes ricinus ticks in Poland

European genospecies of B. burgdorferi sensu lato were identified by examining unfed I. ricinus ticks collected from 10 locations in northwest Poland. Research was conducted using 3 methods: PCR amplification of the fla gene with the FLA1 and FLA2 primer set conserved in all European species of B. burgdorferi sensu lato, PCR-RFLP, and sequencing. There were 5 restriction patterns obtained in this study: 4 characteristic for genospecies B. burgdorferi sensu stricto, B. garinii, B. valaisiana, and B. afzelii and 1 untypical restriction pattern type. PCR products for all restriction patterns were sequenced and sequences have been submitted to GeneBank ( accession numbers: AY603342, AY603343, AY603344, AY603345, AY603346). Polish sequences of the fla gene for B. burgdorferi s.s., B. garinii, B. valaisiana, and B. afzelii were identical with sequences from GeneBank at 99.79%, 99.58%, 100% and 100% respectively. The fifth sequence demonstrated 99.79% identity with sequences of a B. lusitaniae PotiB2 isolate from Portugal, and also clusters with this strain. B. lusitaniae DNA in I. ricinus was detected in 3 out of 10 localities and constituted 5.9% of infected individuals with I. ricinus.