Increased Leptospirosis Abortions Reported in Bluegrass Region

The University of Kentucky's Livestock Disease Diagnostic Center has confirmed 40 cases of equine leptospirosis in the Central Kentucky region from July 2006 until now, compared to two cases in the same time period last year. Researchers will be conducting a Bluegrass-based study on the incidence of equine leptospirosis, as well as a nationwide economic impact study.

According to Craig Carter, DVM, PhD, a professor of epidemiology at the university, the diagnostic center has recorded 38 abortions related to leptospirosis.

Researchers believe the surge of cases might be due to increased rainfall as the bacteria responsible for the disease thrive in wet conditions.

"We hope to gain a clearer picture of how this impacts horses across the U.S.," Carter said. Another reason for the study is to raise awareness of the disease in hope of developing a vaccine. There is no approved leptospirosis vaccine for horses. However, approved vaccines are available for cattle, pigs and dogs.

Equine leptospirosis is caused by a spiral-shaped bacterium. Leptospira bacteria are spread through urine or infected animals and can infect the horse's kidneys. Along with abortion, the bacteria can cause systemic illness that can result in kidney and liver disease. Leptospira can also cause what is known as equine recurrent uveitis, which is an infection of the eye also known as moon blindness. A veterinarian should do a complete physical and ophthalmologic exam when leptospirosis is suspected.

Wild animals, including mice, squirrels, fox, skunks, opossums, and deer maintain the bacteria in nature and are often the source of infection for domestic animals. Domestic species such as cattle, dogs, and pigs can also be a source of infection.

Horses can pick up the bacteria through the skin or mucosal membranes of the eye or mouth if they have contact with blood, urine, or tissues from infected animals. Infection can also occur when horses splash infected urine into their eyes or eat hay or feed contaminated by infected urine.

Carter advised horse owners to minimize contact between their horses and wild animals, and to keep animals away from horses' feed and water sources. Keeping horses and cattle separate is also recommended. Sick horses should be isolated and areas they have accessed disinfected.

According to Carter, the incubation period for the bacteria can be up to 20 days, but can vary depending on the infective dose and the status of the horse's immune system.

About the Author

Erin Ryder

Erin Ryder is a former news editor of The Horse: Your Guide To Equine Health Care.

Stay on top of the most recent Horse Health news with FREE weekly newsletters from Learn More