The health of hedgehogs in relation to tick infestation and transmission of pathogens by the hedgehog tick, Ixodes hexagonus in vitro.

Abstract

Background Hedgehogs and Ixodes hexagonus ticks live in close contact with each other and hedgehogs play a role as reservoir for several pathogens. The hedgehog tick is a vector of a range of different pathogens. This study looks at the possibility of transmission from tick-borne diseases by an in vitro method.

Methods We have submitted questionnaires to hedgehog shelters to find out what clinical symptoms hedgehogs with and without tick infestations show according to hedgehog shelter owners. I. hexagonus will be fed in vitro in order to investigate the possible transmission of pathogens. During this study improvement was trying to be made to the in vitro feeding procedure for optimal feeding results of I. hexagonus ticks, using Dermacentor reticulatus as a control. The original feeding procedure is available at the department of Utrecht University of Tick-borne Diseases. Blood was taken from wells were ticks had fed and this blood was examined by PCR and RLB. Ticks that had fed or died during the in vitro feeding were also examined by RLB.

Results A total of 45 questionnaires were received. These questionnaires showed a variety of clinical symptoms seen in hedgehogs. Attachment rate in the in vitro study was low, only five I. hexagonus attached. Several methods were tested and it appeared to be that fresh hair from hosts of I. hexagonus stimulate the hedgehog tock the most to feed in vitro. Some pathogens were found, such as Borrelia afzelii and Ehrlichia/Anaplasma catch-all in blood samples and Rickettsia catch-all in an I. hexagonus tick. Unfortunately due to contamination Ehrlichia/Anaplasma catch-all was false positive.

Conclusions No definite conclusions could be drawn out of the questionnaires. The questionnaires weld held shortly after hibernation, meaning hedgehogs could be more vulnerable, showing other clinical symptoms than the ones caused by ticks. Beside, questionnaires were filled in based on knowledge by experience, rather than through evidence based papers. No conclusions could be drawn whether hedgehogs could get sick after infestations by Ixodes hexagonus. It is possible for I. hexagonus to transmit pathogens using an in vitro feeding system, but more research is needed to optimize the in vitro feeding assay for I. hexagonus.