Seroprevalence of Babesia infections of dairy cows in northern Thailand

The present study was conducted to demonstrate the epidemiological distribution of bovine babesiosis in the northern regions of Thailand. A total of 700 serum samples of dairy cows in the northern provinces (Chiang Rai, Chiang Mai, Lumpang, and Mae Hong Sorn) were tested for antibodies against Babesia bovis and B. bigemina. Species-specific enzyme-linked (rRAP-1/CTs) were performed. According to the results, 517 (73.8%) and 484 (69.1%) were positive for B. bovis and B. bigemina, respectively. In addition, 370 (52.9%) were positive for mixed infections by both ELISAs. On the other hand, all samples were also examined by the indirect fluorescent-antibody test (IFAT) with B. bovis- and B. bigemina-infected blood smears. According to the IFAT, 482 (68.8%) and 531 (75.8%) were positive for these infections, respectively. The overall concordances between the ELISA and IFAT techniques were 93.6% and 90.7% for B. bovis and B. bigemina infections, respectively. These results indicated that babesia infections are widespread in the northern parts of Thailand. To our knowledge, this is the first report describing the epidemiology of Babesia infections using rRAP-1/CT-based ELISAs in these areas.