First confirmed report of equine coital exanthema in Uruguayan horses

Equine Coital Exanthema (ECE) is a contagious venereal disease caused by Equid alphaherpesvirus 3 (EHV‑3). Although ECE is self-limiting, it causes significant economic losses to the global equine industry due to the temporary segregation of affected mares and stallions from breeding activities. This report describes the epidemiological, clinical, histological, and molecular findings from an outbreak of ECE in Uruguayan horses. Seven days following the introduction of a stallion, five mares developed extensive papular and vesicular dermatitis in the vaginal and perineal regions. The stallion exhibited minimal preputial mucosal ulcerative lesions. Histological examination of skin biopsies from three affected mares revealed ulcerative dermatitis with intranuclear eosinophilic inclusion bodies in keratinocytes. Molecular confirmation of EHV‑3 infection was achieved by qPCR analysis of perineal skin samples from a mare with typical ECE lesions.