A Leptospirosis Outbreak in a Riding Stable in Central Italy.

Leptospirosis is a widespread zoonotic disease of major concern for both veterinary and public health. In horses, it is associated with equine recurrent uveitis, a painful condition that may lead to blindness and affects approximately 10% of the global horse population. In May 2025, following the occurrence of three uveitis cases in a riding stable in Central Italy, 94 equine blood samples were collected and tested using the microscopic agglutination test (MAT) for Leptospira spp. Antibody titres against serogroup Icterohaemorrhagiae were detected in 68 horses (72.4%). An on-site investigation was conducted, and control measures were implemented, including movement restrictions, clinical monitoring of horses, and antibiotic treatment. Follow-up serological testing showed no significant variation in antibody titres, no additional clinical cases were observed in animals, and no symptoms were reported among individuals exposed to the facility. These findings suggest widespread exposure to Leptospira spp. without evidence of ongoing transmission or public health impact. This study highlights the diagnostic and management challenges of equine leptospirosis, together with the importance of surveillance within a One Health framework.