Co-Occurrence of <i>Borrelia burgdorferi</i> Sensu Lato and <i>Babesia</i> spp. DNA in <i>Ixodes ricinus</i> Ticks Collected from Vegetation and Pets in the City of Poznań, Poland

Abstract

Here, we described the prevalence of Borrelia burgdorferi s.l. and Babesia species found in mono- and double infections among Ixodes ricinus ticks occurring in urban areas of the city of Poznań, Poland. We tested 1029 host-seeking ticks and 1268 engorged ticks removed from pet animals. Borrelia afzelii and B. garinii prevailed both in ticks from vegetation (3.7% and 3.7%, respectively) and from pets (3.7% and 0.6%, respectively). Babesia canis and Ba. microti were the most prevalent in host-seeking (2.6% and 1.4%, respectively) and feeding ticks (2.8% and 2.2%, respectively). Babesia microti sequences proved to be identical to the human pathogenic Ba. microti genotype “Jena/Germany”. Sequences of the rarest piroplasm Ba. venatorum (0.7%) were identical with those isolated from European patients. About 1.0% of tested ticks yielded dual infections; in host-seeking ticks, Ba. canis prevailed in co-infections with B. afzelii and B. garinii, whereas Ba. microti and B. afzelii dominated in double-infected feeding ticks. Dual infections, even with a low prevalence, pose a challenge for differential diagnosis in patients with acute febrile disease after a tick bite. The finding of Ba. canis in both tick groups suggests that I. ricinus could be involved in the circulation of this piroplasm.

Keywords

• <i>Ixodes ricinus</i>
• <i>Borrelia burgdorferi</i> s.l.
• <i>Babesia microti</i>
• <i>Babesia venatorum</i>
• <i>Babesia canis</i>
• <i>Borrelia miyamotoi</i>