Serologic and Molecular Diagnosis of and Infection in Dogs in an Endemic Region.

and are obligate intracellular, tick-borne rickettsial pathogens of dogs that may cause life-threatening diseases. In this study, we assessed the usefulness of PCR and a widely used commercial antibody-based point-of-care (POC) test to diagnose and infection and updated the prevalence of these pathogens in dogs inhabiting the Caribbean island of Saint Kitts. We detected in 62/227 (27%), in 84/227 (37%), and the presence of both in 43/227 (19%) of the dogs using PCR. POC testing was positive for in 53/187 (28%), in 112/187 (60%), and for both in 42/187 (22%) of the samples tested. There was only a slight agreement between PCR and POC test results and a fair agreement for PCR and POC test results. Our study suggests that PCR testing may be particularly useful in the early stage of infection when antibody levels are low or undetectable, whereas, POC test is useful when false-negative PCR results occur due to low bacteremia. A combination of PCR and POC tests may increase the ability to diagnose and infection and consequently will improve patient management.