State of Connecticut Mosquito Management Program

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09/10/2024

Connecticut Confirms First Case of Eastern Equine Encephalitis for 2024 in Horse

HARTFORD, Conn. — The Connecticut Department of Agriculture reports the state’s first case this year of Eastern equine encephalitis (EEE) in a domestic animal. EEE was detected in a 23-year-old unvaccinated gelded horse from Fairfield County. Upon examination the horse was exhibiting neurological signs. Diagnostic samples were collected and tested positive for EEE virus.

EEE is not spread by horse-to-horse or horse-to-human contact. It is a viral disease transmitted through the bites of mosquitoes. Horse owners should be alert for EEE even if mosquito testing in the area has not been positive. The risk for mosquito-borne diseases continues until the first hard freeze ends mosquito activity.

“The EEE vaccinations for horses are demonstrably protective, highly effective, and very safe. Horses without a EEE vaccine history have a high mortality rate, upwards of 95%, making it crucial that these be part of every horse’s core vaccine schedule,” stated Connecticut State Veterinarian Erin Masur, DVM. “While horses are most susceptible to EEE, mosquitoes can also transmit the virus to goats, turkeys, chickens, and humans. We urge residents to implement the necessary precautions to protect their animals and themselves.”

The Connecticut Mosquito Management Program is reporting a heightened level of mosquito activity and increased virus detections in comparison to prior years. The Connecticut Agricultural Experiment Station (CAES) has detected EEE-infected mosquitoes in 11 Connecticut towns this year in four different counties – Windham, New London, Hartford and Middlesex. There have been no human cases of EEE confirmed this year in Connecticut.

To reduce the risk of being bitten by mosquitoes, residents should:

  • Minimize time spent outdoors between dusk and dawn when mosquitoes are most active.
  • When it is necessary to be outdoors, use mosquito repellents containing an EPA-registered active ingredient, including DEET, Picaridin, IR3535, oil of lemon eucalyptus, para-menthane-diol (PMD), or 2-undecanone. EPA registration of skin-applied repellent products indicates that they have been evaluated and approved for human safety and effectiveness when applied according to instructions on the label.
  • Wear shoes, socks, long pants, and a long-sleeved shirt when outdoors for long periods of time, or when mosquitoes are more active. Clothing should be light-colored and loose-fitting and made of tightly woven materials that keep mosquitoes away from the skin.
  • Wear clothing and gear treated with permethrin. Permethrin is an insecticide that kills or repels mosquitoes and ticks.
  • Be sure door and window screens are tight-fitting and in good repair.
  • When sleeping outdoors, use tents or mosquito netting in an unscreened structure. Treat camping gear with permethrin when possible.
  • Cover strollers and baby carriers with mosquito nets when outside.

Equine owners are encouraged to implement the following, in coordination with their veterinarian:

  • Administering the initial two-dose vaccine series, four to six weeks apart.
  • Administer regular boosters at least annually.
  • Consult with your veterinarian if boosters are needed every six months.
  • Give vaccinations at least one month prior to mosquito season to develop protective immunity.
  • Remove sources of standing water to eliminate mosquito breeding grounds.
  • Clean and refill water troughs regularly.
  • Apply fly sprays containing pyrethrin regularly.
  • If your horse is showing neurologic signs, i.e., hyperexcitability, tremors, convulsions, paralysis, head tilt, head pressing, incoordination, drowsiness, recumbency, colic, or death, it’s important to call a veterinarian to determine a diagnosis and treatment.

Neurologic diseases of domestic animals, such as EEE, West Nile Virus, and Rabies, are reportable to the State Veterinarian at 860-713-2505. For more information, on animals and animal health, visit the state website.

The Connecticut Department of Agriculture (CT DoAg) mission is to foster a healthy economic, environmental, and social climate for agriculture by developing, promoting, and regulating agricultural businesses; protecting agricultural and aquacultural resources; enforcing laws pertaining to domestic animals; and promoting an understanding among the state's citizens of the diversity of Connecticut agriculture, its cultural heritage, and its contribution to the state's economy. For more information, visit www.CTGrown.gov.

FOR MEDIA INQUIRIES:
Rebecca Eddy, Rebecca.Eddy@ct.gov
860-573-0323
http://www.ctgrown.gov