Distinct combinations of Borrelia burgdorferi sensu lato genospecies foundin individual questing ticks from Europe

The genetic diversity of Borrelia burgdorferi sensu lato was assessed in in dividual adult Ixodes ricinus ticks from Europe by direct PCR amplification of spirochetal DNA followed by genospecies-specific hybridization. Analysi s of mixed infections in the ticks showed that B. garinii and B. valaisiana segregate from B. afzelii. This and previous findings suggest that host co mplement interacts with spirochetes in the tick, thereby playing an importa nt role in the ecology of Lyme borreliosis.