Prevalence of Cytauxzoon felis infection in healthy free-roaming cats in north-central Oklahoma and central Iowa

Case summary Cytauxzoonosis is a tick-borne disease of cats, and Oklahoma (OK), USA, is considered an enzootic state. To determine the prevalence of Cytauxzoon felis, blood was collected from free-roaming cats, as they are frequently exposed to tick vectors. Our objective was to determine the prevalence of C felis infection in free-roaming cats in north-central Oklahoma and central Iowa (IA). Infection with C felis was determined using DNA extracted from blood and PCR amplification. Blood was collected from 380 free-roaming cats between January and April in 2014 in OK. DNA from C felis was detected in 3/380 (0.8%; 95% confidential interval [CI] 0.22–2.3%). In IA, 292 blood samples were collected between 2012 and 2014. No C felis-infected cats were detected (0; 95% CI 0–0%). Relevance and novel information The prevalence of C felis (0.8%) in north-central OK reported herein was lower than the previously reported 3.4% in domestic cats in OK. Our study supports that the prevalence in a given enzootic area can vary by location and from the pool of cats sampled. None of 291 (0%) cats were infected with C felis in central IA. To date, only one case of cytauxzoonosis in a domestic cat has been reported in IA. It is important to monitor cats for C felis infections in northern US states, as geographic distribution of Amblyomma americanum expands northward. As free-roaming cats have more contact with the tick vectors of C felis, this population allows us to monitor the expansion of C felis distribution.