Babesia caballi and Theileria equi in ticks from horses in four Indigenous communities of Costa Rica.

Abstract

BACKGROUND: Equine piroplasmosis, caused by Babesia caballi and Theileria equi, is endemic in Costa Rica. However, the presence of these hemoparasites in tick vectors has not been documented in the country. AIMS/OBJECTIVES: To identify tick species infesting horses in four Indigenous communities and to determine the presence of B. caballi and T. equi DNA in ticks from piroplasmosis-positive horses. METHODS: Ticks (n = 1063) were collected from 129 horses in four Indigenous communities. Species identification and sex classification were performed. From 76 PCR-positive horses, 203 ticks were analyzed for B. caballi and T. equi using nested PCR. Two positive samples were sequenced and compared to GenBank entries. RESULTS: Dermacentor nitens was the predominant tick (90.3 %), followed by Amblyomma mixtum (9.7 %). Theileria equi was detected in ticks from 55.3 % of positive horses; B. caballi was only found in coinfection with T. equi. Sequences showed 99 % similarity with GenBank references. CONCLUSION: This is the first report of B. caballi and T. equi DNA detection in ticks from Costa Rica. Dermacentor nitens and A. mixtum are implicated in potential transmission. Surveillance and tick control are important in Indigenous communities to prevent the spread of pathogens. The study was based on tick samples collected in 2011; thus, results reflect the situation at that time. Updated surveillance and vector competence studies are needed to support equine health and One-Health efforts in Indigenous regions of Costa Rica.