Ticks in urban dogs in the Netherlands: Prevalence and life stages in different urbanisation areas, a pilot study

Abstract

Background: Ticks play an important role as vector of zoonotic and species-specific pathogens. Ticks are also found in urbanized areas, but how they get there is largely unknown. Small rodents and hedgehogs are considered to be able to maintain the tick life cycle in cities, but alternative explanation is a continuous importation via animals. Objective: to evaluate a research approach that would enable us to determine to the role of dogs in these two processes. Method: Ticks were collected from dogs that resided at different urban areas in the city of Utrecht and examined for their life stage. The walking routes of the dogs were tracked using a GPS-unit and the correlation between walking distances and different urban areas was calculated. Results: Fifteen dogs participated in the study. In total 11 nymphs (33%) and 22 adult ticks (67%) were found on 11 dogs (73%), in average 2.2 ticks per dog. Ticks were probably most contracted in urban parks, 1st and 2nd degree of urbanisation areas and outside the city. There was no correlation between tick counts and walking distances in different areas, dogs on the leash, walking outside the city or in their own neighbourhood. Both nymphs and adults were found in the city. Conclusion: The research approach worked well, but application of the GPS-unit needs further improvement. The presence of ticks on dogs that remained in the urban areas, shows that this approach can be used to identify locations in cities with ticks.