Triple E Virus Deadly To Horses And Humans

Summer brings a heightened risk of mosquito borne illnesses. Eastern Equine Encephalitis is one of the most deadly. Known as triple E (EEE) or sleeping sickness and commonly associated with horses, this disease causes brain inflammation and kills about a third of humans who contract it.

 

While there is no vaccine for humans, there is little reason for a horse to contract the disease because a safe and inexpensive vaccine is available. Dr. Courteney Holland, an Alabama Extension animal scientist, says horse owners should remember to vaccinate their animals every year.

 

“Horse owners should vaccinate their horses twice a year for sleeping sickness,” said Holland. “The best time of year to revaccinate is mid- to late-summer, such as August or September when some cases of EEE are seen in Alabama.”

 

EEE is a viral disease spread by certain kinds of mosquitoes and is almost always fatal in horses. It is characterized by the progressive failure of the horse’s central nervous system. Symptoms in horses, include depression, high fever, hypersensitivity to sound and touch, apparent blindness, wandering and paralysis. The horse is a terminal host for the virus and cannot spread the disease to humans or other animals.

 

There is not much an owner can do once their horse develops EEE. The mortality rate is 75 to 100 percent. Holland said if they do survive, they will show gradual improvement of function over weeks to months but the horse may never recover fully.

 

“Horses will have immunity from this disease for up to two years after infection, but may have permanent brain damage,” said Holland. “It is usually recommended to put the horses down even if the disease doesn’t kill them, because of the neurological damage.

 

To reduce exposure to mosquitoes for both humans and horses, eliminate the breeding

grounds for mosquitoes. (Mosquitoes can breed in any source of water that lasts more than four days.) Do not allow buckets, wheel barrows, old tires and watering troughs to collect water. Store these items in a barn or garage or turn them over if they must be left outside so they do not collect water. For watering troughs, be sure to empty out the water every few days to help reduce the risk. Another control measure is using insect repellents on yourself and horses. This may help slow the spread of the disease. Horse owners may want to stable their animals to limit their exposure to mosquitoes.