The natural infection of birds and ticks feeding on birds with Rickettsia spp. and Coxiella burnetii in Slovakia

Abstract

Ixodid ticks (Acari: Ixodidae) are known as primary vectors of many pathogens causing diseases in humans and animals. Ixodes ricinus is a common ectoparasite in Europe and birds are often hosts of subadult stages of the tick. From 2012 to 2013, 347 birds belonging to 43 species were caught and examined for ticks in three sites of Slovakia. Ticks and blood samples from birds were analysed individually for the presence of Rickettsia spp. and Coxiella burnetii by PCR-based methods. Only I. ricinus was found to infest birds. In total 594 specimens of bird-attached ticks were collected (451 larvae, 142 nymphs, 1 female). Altogether 37.2% (16/43) of bird species were infested by ticks and some birds carried more than one tick. The great tit, Parus major (83.8%, 31/37) was the most infested species. In total, 6.6 and 2.7% of bird-attached ticks were infected with Rickettsia spp. and C. burnetii, respectively. Rickettsia helvetica predominated (5.9%), whereas R. monacensis (0.5%) was only sporadically detected. Coxiella burnetii was detected in 0.9%, Rickettsia spp. in 8.9% and R. helvetica in 4.2% of bird blood samples. The great tit was the bird species most infested with I. ricinus, carried R. helvetica and C. burnetti positive tick larvae and nymphs and was found to be rickettsaemic in its blood. Further studies are necessary to define the role of birds in the circulation of rickettsiae and C. burnetii in natural foci.

Diverse tick-borne microorganisms identified in free-living ungulates in Slovakia

“…However, there is no evidence of the involvement of large ungulates in the life-cycle of the pathogen in this country [146, 147]. Natural infections with C. burnetii have been detected in ticks (questing or feeding on different hosts) from different countries [53, 148] including Slovakia [74, 147, 149, 150], whereas transmission of the Q fever agent to humans via a tick bite is rare [53]. Based on our detections of C. burnetii in all developmental stages of I. ricinus that were collected from large ungulates we assume that similarly as for SFG rickettsiae, ungulates serve only as vehicles for the transport of infected ticks.…”

Approaches for Reverse Line Blot-Based Detection of Microbial Pathogens in Ixodes ricinus Ticks Collected in Austria and Impact of the Chosen Method

“…Few other studies have investigated I. ricinus ticks for the presence of C. burnetii and either could not detect this microorganism (71,72) or detected it in very low numbers (73). Nevertheless, in Austria, C. burnetii was detected in Tyrol in 1994 by use of the hemocyte test (20), a commonly used method for detection of rickettsiae and Rickettsialike organisms in the hemolymph of ticks.…”

Trends in tick population dynamics and pathogen transmission in emerging tick-borne pathogens in Europe: an introduction

“…The work by Berthová et al (2016, this issue) focuses on the role of birds in the circulation of rickettsiae and Coxiella burnetii in natural foci (Berthová et al 2016). They studied the natural infection of birds and (mostly immature) I. ricinus ticks that fed on birds with Rickettsia spp.…”