Red Foxes ( Vulpes vulpes ) Are Exposed to High Diversity of Borrelia burgdorferi Sensu Lato Species Infecting Fox-Derived Ixodes Ticks in West-Central Poland.

The role of red fox, Vulpes vulpes , and its associated ticks in maintaining Borrelia burgdorferi sensu lato (s.l.) was studied. A total of 1583 ticks were removed from ears of 120 infested animals and were identified as species using a nested PCR targeting the ITS2 and coxI fragments of Ixodes DNA. Ixodes kaiseri prevailed (76%), followed by I. canisuga , I. ricinus , and I. hexagonus . In total, 32.4% of 943 ticks revealed Borrelia DNA and 10 species of B. burgdorferi s.l. complex were identified. Borrelia garinii and B. afzelii comprised 70% of all infections. The other eight species included B. americana, B. bissettiae , B. burgdorferi sensu stricto (s.s.), B. californiensis, B. carolinensis , B. lanei , B. spielmanii , and B. valaisiana . Analysis of tissues from 243 foxes showed that 23.5% were infected with B. burgdorferi s.l. Borrelia garinii was detected in 91% of the infected animals, including 31% of mixed infections with B. afzelii , the second most prevalent species, followed by B. spielmanii . The predominance of B. garinii in PCR-positive animals and infected larval ticks (38.1%), suggests that this spirochete and B. afzelii are preferentially associated with foxes. Although red foxes are exposed to a high diversity of B. burgdorferi s.l. species found in engorged Ixodes ticks, their reservoir competence for most of them appears to be low.