EN
Recently, on the basis of molecular analysis, the number of B. burgdorferi sensu lato genomic groups has been extended to eight. The aim of our studies was to identify B. burgdorferi sensu lato strains isolated from ticks and dogs in Poland on the basis of fragment length polymorphism of rrf (5S)-rrl (23S) intergenic spacer amplicons. The analysis of amplicon sizes revealed that two Polish tick-originated strains: 236/2 and KL43 represent B. lusitaniae genogroup; strain KL5 - B. afzelii; strains KL44, KL93 and KL1 - B. burgdorferi sensu stricto. Strain KL3 and KL4 may represent a separate genogroup of B. burgdorferi. Three strains isolated from dogs (P3, P4 and P6) with the amplicon sizes of 267 bp, 262 bp and 262 bp respectively, form a coherent cluster.