The exact causes of equine recurrent uveitis (ERU) confounded veterinarians and researchers alike for many years. While they’ve made great strides in determining what’s behind this painful, blindness-causing condition, some questions still exist. For instance, does the bacteria known to play a role in ERU development in U.S. horses—Leptospira spp—impact horses in other countries, as well? As it turns out, not necessarily.

A group of researchers in the United Kingdom recently evaluated Leptospira’s role in ERU in their region. They had four main goals:

• Establish Leptospira prevalence in ERU horses;
• Identify which strains of the bacteria are most commonly involved;
• Compare blood serum and aqueous humor (the fluid that fills the eye) antibody levels; and
• Evaluate the efficacy of serology alone as a confirmatory test.

“We had a feeling that Leptospira-associated uveitis is less prevalent here than in other parts of the world, particularly when you compare the situation here with what is published in the United States and Continental Europe, where the prevalence of uveitis in general is much higher,” said Fernando Malalana, DVM, Dipl. ECEIM, FHEA, MRCVS, RCVS, European Specialist in Equine Internal Medicine, from the University of Liverpool Equine Hospital