Ticks and Tick-Borne Pathogens Encountered by Dogs and Cats: A North European Perspective

Area of Science:

• Veterinary Entomology
• Epidemiology
• Parasitology

Background:

• Climate change is escalating the global prevalence of tick-borne diseases (TBDs).
• Finland has observed a rise in human borreliosis cases, suggesting increased tick exposure.
• Canine and feline TBD cases are not systematically tracked in Finland, impeding trend analysis.

Purpose of the Study:

• To determine the prevalence and types of tick-borne pathogens (TBPs) in ticks removed from dogs and cats in Finland.
• To map the spatial distribution of these pathogens nationally.
• To assess the exposure of Finnish pets to ticks and associated diseases.

Main Methods:

• Crowdsourced tick samples (3697 Ixodes ricinus, 2355 Ixodes persulcatus) from dogs and cats were collected.
• Ticks were screened for Borrelia spp., Rickettsia spp., Anaplasma phagocytophilum, Neoehrlichia mikurensis, Babesia spp., Francisella tularensis, Bartonella spp., and tick-borne encephalitis virus (TBEV) using qPCR.
• Pathogen occurrence was mapped across Finnish administrative regions.

Main Results:

• Adult ticks (99%) were predominantly found on pets.
• Prevalence rates in adult ticks: Borrelia (26.2%), Rickettsia (9.3%), Anaplasma phagocytophilum (1.1%), TBEV (1.1%), Neoehrlichia mikurensis (0.6%), Babesia (0.4%).
• Borrelia and Rickettsia were detected nationwide; other pathogens showed sporadic distribution. Bartonella and F. tularensis were not detected.

Conclusions:

• Dogs and cats in Finland are frequently exposed to ticks carrying a variety of pathogens.
• The widespread presence of Borrelia and Rickettsia necessitates promoting tick protection measures for pets.
• The high proportion of adult ticks on pets raises questions about their role in tick population dynamics.