Diversity of Borrelia genospecies in Ixodes ricinus ticks in a Lyme borreliosis endemic area in Switzerland identified by using new probes for reverse line blotting

In Europe 7 Borrelia species belonging to the Borrelia burgdorferi sensu lato complex have been reported in Ixodes minus ticks In addition another Borrelia related to the relapsing fever spirochaetes has also been described In the present study we designed probes for reverse line blotting allowing detection and identification of all these Borrelia species after amplification of the variable spacer region between the 23S and 5S ribosomal genes These new probes allowed us investigate the diversity of Borrelia in 915 I ricinus collected on the south-facing slope of Chaumont (Switzerland) Among the 159 infected ticks 7 Borrelia species were identified and B spielmanii and relapsing fever-like (RFL) spirochaetes were identified in this area for the first time B valaisiana and B spielmanii were significantly less present in male than in female or nymphal ticks Mixed infection with RFL spirochaetes and Lyme borreliosis spirochaetes were detected in 4 ticks In addition the set of probes could identify the recently described species B bavariensis (C) 2009 Elsevier GmbH All rights reserved