Clinical and Subclinical Cases of Canine Babesiosis Caused by Babesia gibsoni in the Republic of Korea

Canine babesiosis has been scarcely investigated in the Republic of Korea (ROK). Although it is known that Babesia gibsoni is its primary causative agent, its clinical presentation has not been completely clarified in the ROK. Consequently, the aim of this study was to evaluate the clinical appearance of this parasitic infection based on the anamnesis of the patient and compare of hematological and biochemical test results. Four hundred whole blood samples from patients with a presumptive diagnosis of tick-borne disease were analyzed by polymerase chain reaction (PCR) to amplify the Babesia spp. 18S rRNA gene and by a rapid diagnostic test kit (VetAll Laboratories^®) to detect B. gibsoni seroreactive animals. Thirty-six (9.0%) dogs were PCR-positive but only 24 (6.0%) were seropositive. The investigation revealed that all the courses of the disease are present in the ROK, with the acute course being predominant. The acute course tends to consist of inappetence, lethargy, pyrexia, gastrointestinal symptoms, and occasionally hematuria. It also occurs with common hematological abnormalities, such as thrombocytopenia and anemia, and to a lesser extent biochemical abnormalities, such as hyperbilirubinemia, hypoalbuminemia, and elevated liver enzymes. This research shows that B. gibsoni is an endemic hemoparasite capable of producing a variety of clinical manifestations in dogs. For its accurate diagnosis, a descriptive history of the clinical signs, hematology, and biochemical profile of the patient, along with a well-performing PCR assay, are essential. These findings will help in planning pragmatic preventive strategies against this potent threat in the ROK.