Zoonotic Peculiarities of Borrelia burgdorferi s.l.: Vectors Competence and Vertebrate Host Specificity

Tick-borne diseases are of increasing public health concern because of range expansions of both vectors and pathogens (Daniel et al., 2003). Lyme borreliosis is the most common arthropod-borne human disease in temperate regions of the northern hemisphere. The causative agents of Lyme borreliosis (and other tick-borne borrelioses) are spirochaetes belonging to the Borrelia burgdorferi sensu lato (s.l.) species complex. It is well known that B. burgdorferi are unique among the pathogenic spirochaetes by requiring obligate bloodfeeding arthropods for their transmission and maintenance in vertebrate host populations. All known causative agents of borrelioses circulate between ticks (Arachnida, Acari, Ixodoidea) and wide variety of vertebrates species (mammals, birds and reptiles). Consequently, Borrelia populations are shaped by the dynamics and demographic processes of host and vector populations, host and vector immune responses and extrinsic abiotic factors (e.g. combination of temperature, humidity and types of climate and landscape) affecting host and vector populations (Margos et al., 2011).