Investigating the presence of equine piroplasmosis in Ireland.

Background Equine piroplasmosis (EP) is a notifiable disease in Ireland and a significant concern to domestic and international equine industries. Information regarding EP presence in Ireland is currently limited. This retrospective surveillance study describes a serological and molecular analysis of blood samples submitted to the Irish Equine Centre for EP testing between January 2013 and April 2016. Methods Following serological testing, seropositive samples were screened using a PCR targeting the 18S ribosomal RNA gene. Amplicon sequences were bioinformatically analysed to identify the parasite species and to assess genetic diversity. Results From 2099 screened equine blood samples, 2.5 per cent and 1 per cent were seropositive for Theileria equi and Babesia caballi, respectively. T equi DNA was detected in 9 per cent of the seropositive samples while B caballi DNA was not detected in any sample. The T equi DNA sequences displayed no genetic diversity at this locus, in contrast to samples from the UK and from endemic areas. Conclusion Detection of EP-seropositive and parasitaemic horses in Ireland indicates a clear and present health risk to the equine population. It is recommended that owners adopt appropriate biosecurity measures and that clinicians are mindful of this disease as a differential diagnosis.