Retrospective Evaluation of Vector-borne Infections in Cats Living in Germany (2012-2020)

Background: Blood-feeding arthropods can transmit parasitic, bacterial, or viral pathogens to domestic animals and wildlife. Vector-borne infections are gaining significance due to the increase of travel, import of domestic animals from abroad, and due to the changing climate in Europe. The main objective of this retrospective study was to assess the prevalence of some vector-borne infections in cats in which a ‘Feline Travel Profile’ had been conducted. Methods: This retrospective study included test results from cats for which a ‘Feline Travel Profile’ established by the laboratory LABOKLIN had been requested by veterinarians in Germany between April 2012 and March 2020. This above-mentioned diagnostic panel contains direct detection methods via PCR for Hepatozoon spp. and Dirofilaria spp. as well as indirect detection methods via IFAT for Ehrlichia spp. and Leishmania spp. The profile was expanded to include an IFAT for Rickettsia spp. from July 2015 onwards. The prevalence of the different vector-borne infectious agents was calculated. Results: A total of 624 cats were tested using the ‘Feline Travel Profile’. Serological samples for indirect detection methods were available for all 624 cats, EDTA-samples for direct detection methods for 618 cats. Positive test results were as follows: Ehrlichia spp. IFAT 73 out of 624 (12%), Leishmania spp. IFAT 22 out of 624 (4%), Hepatozoon spp. PCR 53 out of 618 (9%), Dirofilaria spp. PCR 1 out of 618 cats (0.2%) and, tested from July 2015 onwards, Rickettsia spp. IFAT 52 out of 467 cats (11%). At least one infection was present in 175 out of 624 cats. Three coinfections were detected before 2015; after including the Rickettsia spp. test results there were 19 cats with confections (in 14 out of these 19 cats Rickettsia spp. were involved).Conclusions: 175 out of 624 cats (28%) were tested positive for at least one vector-borne pathogen. Infections with multiple pathogens could be detected in 4% of the cats from 2012 to 2020. The data emphasizes the importance of considering the above-mentioned vector-borne infections as potential differential diagnoses in cats.