The prevalence of Rickettsia felis DNA in fleas collected from cats and dogs in the UK

In a large-scale survey in the UK, recruited veterinary practices were asked to inspect client-ownedcats and dogs, selected at random between April and June 2018, following a standardised flea inspection protocol. A total of 326 veterinary practices participated and 812 cats and 662 dogs were examined during the 3-month period. Fleas were collected, identified to species level and fleas of the same species collected from a single animal were pooled together and treated as a single sample. A total of 470 pooled flea samples were screened by PCR and DNA sequence analysis for a subset of Rickettsia species including R. felis and R. typhi. On analysis, 27 (5.7%) of the pooled flea samples were positive for R. felis DNA; these were predominantly in the cat flea, Ctenocephalides felis, but one dog flea, Ctenocephalides canis was also positive for this pathogen.