Global ecology and epidemiology of Borrelia garinii spirochetes

摘要

Lyme borreliosis (LB) is the most common vector-borne disease in the northern hemisphere. The multisystem illness is due to infection by Borrelia burgdorferi sensu lato (s.l.) bacteria, spread by different Ixodes ticks. In Northern America, only B. burgdorferi sensu stricto (s.s.) is regularly isolated from human patients. However, on the Eurasian continent, the situation is more complex because three different species cause the disease, namely Borrelia afzelii, B. garinii, and B. burgdorferi (s.s.) (1). In addition, these species are spread by different vectors, Ixodes ricinus in Europe and I. persulcatus in Asia. The habitats of these two tick species overlap in Eastern Europe (2). Also, the reservoir hosts for the three species are different. B. afzelii depend on various rodents as their main reservoir host, whereas B. garinii mainly depend on birds. B. burgdorferi s.s., on the other hand, appear to be more of a generalist and can use both birds and rodents as its reservoir host (3).