Aug. 03, 2011. The New York State Department of Agriculture and Markets (NYSDAM), has confirmed 2011's first case of Eastern Equine Encephalitis in Oneida County, NY. The nine year old mare, who had no history of travel, had not been vaccinated against the virus and subsequently died.
EEE poses high mortality rate
EEE is a brain disease transmitted to equines and humans by infected mosquitoes. Commonly called sleeping sickness or Triple E, the virus boasts a high mortality rate. While the virus cannot spread from horse-to-horse or horse-to-human, NYSDAM says, "The presence of an infected horse in the area indicates that mosquitoes carrying EEE are present and pose a threat to both humans and horses."
The Centers for Disease Control (CDC), reports that although EEE infection in humans is rare, the virus is considered to be one of the more serious mosquito-borne diseases in North America. Between 1964 and 2010 says the CDC, cases of EEE in humans across the Eastern US, have varied, "Markedly from year to year." In 2005, for example, 21 cases across the US were confirmed, yet in 2007 only three cases were diagnosed.
The highest number of reported cases up until 2010, has been recorded in Florida, with 70 cases in total confirmed. Massachusetts is second with 37 cases, and Georgia with 28 cases, third. Invariably, adds the CDC, "EEEV transmission is most common in and around freshwater hardwood swamps in the Atlantic and Gulf Coast states and the Great Lakes region."
Symptoms of EEE in humans and equines
EEE infection can result in two types of illness, systemic or encephalitic. In systemic infections, symptoms progress rapidly and include chills, fever, joint aches, weakness and muscle pain. Lasting 1-2 weeks, recovery is usually complete. In encephalitic infection, onset is rapid in infants but in older children and adults, the disease typically develops after a systemic illness.
Encephalitic infections presents symptoms that are far more severe. Alongside a feeling of having the flu, anorexia, vomiting, diarrhea, cyanosis, convulsions, and even coma can occur. This more severe type of EEE, kills approximately one third of all people who contract the disease.
In horses, says NYSDAM, "Typical symptoms of encephalitis include staggering, circling, depression, loss of appetite and sometimes fever and blindness." In many equine cases, an EEV infection is almost always fatal. It is also preventable in horses who have been vaccinated against EEV, although no vaccine currently exists for humans.
First case urges caution
The first confirmed case of EEE in 2011 should put horse owners and the general public on notice cautions NYSDAM. Commissioner of Agriculture and Markets, Darrel J. Aubertine, said it is important to remember, "That West Nile Virus causes neurologic symptoms similar to EEE and is also spread by mosquitoes. All horse owners [should] discuss vaccination against both diseases with their veterinarian."
For human EEE prevention, the CDC recommends reducing exposure to mosquitoes by implementing the following procedures: use insect repellent containing DEET; wear protective clothing; install screens on windows and keep mosquitoes from laying eggs by reducing areas of stagnant water near the home. For further information on Eastern Equine Encephalitis, visit Cdc.gov.
Update: August 12, 2011
On August 11, a horse in Dunn County, Wisconsin, tested positive for EEE and two alpacas have died as a result of the disease. The animals tested positive for the virus on Aug. 09. Wisconsin endured a major outbreak of EEE in 2001 with an estimated 69 cases of the disease.
Elizabeth Batt - Elizabeth Batt is a former large animal nurse, certified NREMT, lover of equines and conservationist.
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