An outbreak of equine influenza has led to a farm in Washington state being quarantined and serves as a reminder to regularly vaccinate horses who travel and  practice biosecurity while at—and after returning from—events and competitions.

The farm in Thurston County is under voluntary quarantine as of November 3 after three horses tested positive for equine influenza, according to the Equine Disease Communication Center (EDCC). Horses from the farm had recently traveled to a barrel race then returned home to infect others, according to information on the EDCC website.

A highly contagious viral disease, equine influenza spreads from contact with contaminated surfaces and through airborne droplets exhaled by an infected horse. With a longer incubation period, several horses on a farm can be infected before the first horse begins to show signs of being ill.

The American Association of Equine Practitioners (AAEP) lists equine influenza among risk-based vaccinations, which are recommended for horses deemed to be more likely to come in contact with the disease, such as those who travel to shows and events.

Click here to read more about equine influenza. 

In addition to vaccination, basic biosecurity measures can protect your horse from  equine influenza, including limiting direct contact with unfamiliar horses while away from home and not using communal water troughs. Once you return from an event, keep the travelers separate from the rest of the horses on the property for at least a week, if possible, to allows signs of illness to be detected.

The Washington State veterinarian is currently working with a private veterinarian to further contain the Thurston County outbreak.