Presence of host-seeking Ixodes ricinus and their infection with Borrelia burgdorferi sensu lato in the Northern Apennines, Italy

Abstract

Host-seeking ticks were collected in the Northern Apennines, Italy, by dragging at 35 sites, at altitudes ranging from 680 and 1670 m above sea level (asl), from April to November, in 2010 and 2011. Ixodes ricinus (4431 larvae, 597 nymphs and 12 adults) and Haemaphysalis punctata (11,209 larvae, 313 nymphs, and 25 adults) were the most abundant species, followed by Haemaphysalis sulcata (20 larvae, five nymphs, and 13 adults), Dermacentor marginatus (42 larvae and two adults) and Ixodes hexagonus (one nymph). Greatest numbers of ticks were collected at locations characterised by southern exposure and limestone substratum, at altitudes <1400 m asl; I. ricinus was most abundant in Turkey oak (Quercus cerris) wood, whereas H. punctata was mostly collected in hop hornbeam (Ostrya carpinifolia) wood and on exposed rocks. Ixodes ricinus was also found up to 1670 m asl, in high stand beech (Fagus sylvatica) wood. The overall prevalence of Borrelia burgdorferi sensu lato (sl) in 294 host-seeking I. ricinus nymphs was 8.5 %. Borrelia garinii was the most frequently identified genospecies (64.0 % of positive nymphs), followed by B. valaisiana, B. burgdorferi sensu stricto, B. afzelii, and B. lusitaniae. Based upon the comparison with the results of previous studies at the same location, these research findings suggest the recent invasion of the study area by the tick vector and the agents of Lyme borreliosis.

Importance of Common Wall Lizards in the Transmission Dynamics of Tick-Borne Pathogens in the Northern Apennine Mountains, Italy

“…It was not possible to identify the genospecies in one positive larva. The obtained sequences were 100% identical to those previously detected in questing ticks in the study area [40]. The seven positive ticks were collected from six lizards, since one lizard hosted one larva and one nymph, both positive to B. lusitaniae.…”

“…Contrarily to this older study, we registered an overall lower I. ricinus infestation prevalence in lizards, lower mean numbers of ticks per lizard, and we detected a higher I. ricinus aggregation. These differences may be due to the recent spread of I. ricinus in the Northern Apennines [40], with a consequent lower tick burden, and to the major environmental variability and harsher climatic conditions in this mountain area, which could lead to a more heterogeneous frequency of questing ticks.…”

“…The research was carried out on the Tuscan side of the TuscanEmilian Apennine National Park, Lucca province, Italy (44°1 2′ N, 10°22′ E) [40]. Podarcis muralis and Lacerta viridis (Laurenti 1768) are the two Lacertidae reported in the study area [2].…”

“…Our previous studies showed the existence of a complex vertebrate-tick-microbial community in the area. Indeed, I. ricinus, which recently colonized the territory, coexists with I. trianguliceps, Dermacentor marginatus, Haemaphysalis sulcata and H. punctata [30,40]. A focus of transmission of Rickettsia slovaca and Electronic supplementary material The online version of this article (doi:10.1007/s00248-017-0994-y) contains supplementary material, which is available to authorized users.…”

“…Moreover, B. burgdorferi s.l. infects questing I. ricinus, and tissues and ticks from small rodents [32,40].…”