Background: As there is little data on vector-borne diseases of cats in the Caribbean region and even around the
world, we tested feral cats from St Kitts by PCR to detect infections with Babesia, Ehrlichia and spotted fever group
Rickettsia (SFGR) and surveyed them for antibodies to Rickettsia rickettsii and Ehrlichia canis.
Results: Whole blood was collected from apparently healthy feral cats during spay/ neuter campaigns on St Kitts in
2011 (N = 68) and 2014 (N = 52). Sera from the 52 cats from 2014 were used to detect antibodies to Ehrlichia canis
and Rickettsia rickettsii using indirect fluorescent antibody tests and DNA extracted from whole blood of a total of
119 cats (68 from 2011, and 51 from 2014) was used for PCRs for Babesia, Ehrlichia and Rickettsia. We could not
amplify DNA of SFG Rickettsia in any of the samples but found DNA of E. canis in 5% (6/119), Babesia vogeli in 13%
(15/119), Babesia gibsoni in 4% (5/119), mixed infections with B. gibsoni and B. vogeli in 3% (3/119), and a poorly
characterized Babesia sp. in 1% (1/119). Overall, 10% of the 52 cats we tested by IFA for E. canis were positive while
42% we tested by indirect fluorescent antibody (IFA) for R. rickettsii antigens were positive.
Conclusions: Our study provides the first evidence that cats can be infected with B. gibsoni and also indicates that
cats in the Caribbean may be commonly exposed to other vector-borne agents including SFGR, E. canis and B.
vogeli. Animal health workers should be alerted to the possibility of clinical infections in their patients while public
health workers should be alerted to the possibility that zoonotic SFGR are likely circulating in the region
