Seventy-eight horses with nonhealing ocular disease examined at Equine Clinic of University of Veterinary Medicne and Pharmaceutical Sciences, Brno, Czech Republic, between years 2009 and 2016, were included in this study. Out of these, 12 horses suffered from bilateral ocular disease and in seven horses antivirotic treatment had been started before the referral, so the contralateral healthy eye was sampled as well. Together 97 dry sterile conjunctival sac cotton swabs were taken. Starting form 2014, peripheral blood leukocytes has been also examined together with ocular swabs. PBLs were examined in 43 patients. Positive EHV-2 results were detected in 53 ocular swab samples (54, 64%) and in 22 out of 43 PBLs samples (51, 16%). Horses were divided into three groups regarding the age. Group of young horses (0 ≤ 3 years), group of middle age horses (315), containing 10, 57 and 11 horses, with 15, 68 and 14 examined eyes respectively. Depending on clinical presentation, horses were also divided into nonulcerative or ulcerative keratitis, keratouveitis, keratoconjuctivitis or corneal degeneration groups.