Ticks and diseases found on dogs and cats in France

Abstract

BACKGROUND: Documented changes in spatial and seasonal tick distribution highlight the importance of continuous surveillance. This paper documents results of a year-round sampling campaign in France, including identification of ticks and associated pathogens recovered from dogs and cats, as part of the European project "Protect Our Future Too." METHODS: Ticks were collected from dogs and cats presented to 35 veterinary practices from 27 administrative French departments between April 2021 and July 2022. DNA extracted from each tick sample was amplified by polymerase chain reaction (PCR) for simultaneous detection of 18 types of protozoan or bacterial microorganisms. RESULTS: Among 777 collected ticks, 6 species were morphologically identified in descending prevalence order as: Ixodes ricinus (58.3%), Dermacentor reticulatus (24.2%, mainly on dogs), I. hexagonus (7.2%, mainly on cats), Rhipicephalus sanguineus sensu lato (3.6%, mainly on dogs), I. canisuga (one tick collected from a cat), and Haemaphysalis punctata (one tick from a dog). Geographical distribution varied by tick species: I. ricinus and D. reticulatus were more frequent in northeast France, whereas R. sanguineus (s.l.) was predominant in southeast France. Ticks were collected throughout the study period but peaked in spring and early summer for I. ricinus and late winter and spring for D. reticulatus. The ticks R. sanguineus (s.l.) were collected only during summer. In total, 71.0% of the ticks were positive for DNA of at least one microorganism. Anaplasma bacteria were most frequent (up to 75.3% in I. ricinus) followed by Rickettsia (up to 49.5% in D. reticulatus). Piroplasm DNA (Babesia/Theileria/Cytauxzoon spp.) was found in 6.4% of I. ricinus, 5.3% of D. reticulatus, and 3.6% of both I. hexagonus and R. sanguineus (s.l). Borrelia burgdorferi sensu lato DNA was detected in 10.2% of I. ricinus. Mycoplasma haemominutum/haematoparvum DNA was detected in 21.8% of D. reticulatus, whereas M. turicensis DNA was detected in 14.3% of I. hexagonus. CONCLUSIONS: Results of this study show that ticks are a year-round risk for dogs and cats in France, and tick-borne pathogens are present as mono- or coinfections at high frequencies. Tick control recommendations for veterinarians and dog and cat owners should incorporate these risks.