DNA isolation was done by using the Maxwell 16 Instrument and System (Promega, Madison, WI, USA). Tissue samples were 3×3×3 mm. To detect B. burgdorferi s. l., we used 2 PCR protocols. The fi rst was a nested PCR done according to the method of Rijpkema et al. (7) . The target for the PCR was the spacer region between 5S and 23S rRNA genes of B. burgdorferi s. l. The nested primers generated a product of 226 bp. The amplifi ed products were analyzed by agarose gel electrophoresis. The second protocol, a LightCycler-PCR hybridization assay (Roche Diagnostics, Mannheim, Germany) (8), simultaneously detects and genotypes the 3 genomic groups of B. burgdorferi s. l. This assay was specifi c for B. burgdorferi senso stricto, B. garinii, and B. afzelii (8) but also amplifi ed B. spielmanii and B. valaisiana. The target for the PCR was the OspA gene.