Eastern Equine Encephalitis Virus found in local mosquito

Posted September 13, 2021 at 2:57 pm     Category: News ReleasePublic Health

*This press release has been updated to reflect the correct location of the positive EEE pool. The state informed New Hanover County on September 16 that the CDC lab made a clerical mistake in the mosquito pooling report that was sent to the county, and the positive pool was not a Culex nigripalpus pool at Fort Fisher in Kure Beach, but was actually a Culiseta melanura pool at Marathon in North Castle Hayne. This updated information should ease public concerns because the Culiseta melanura mosquito species bites birds almost exclusively, and rarely bites humans. Birds are a main reservoir for EEE transmission, which is how it was likely transmitted and then found within the sample. In addition, the Marathon trap is along a stream deep in the woods with little human population. Horse farms in the North Castle Hayne area are encouraged to be proactive and ensure their horses have received the EEE vaccine. The American Association of Equine Practitioners (AAEP) recommends horses be vaccinated annually, at a minimum and additional information about EEE in horses can be found here.

NEW HANOVER COUNTY, NC – Recent testing of mosquitoes by New Hanover County Public Health confirmed one positive sample of Eastern Equine Encephalitis Virus (EEEV) in a mosquito pool from a trap in North Castle Hayne*. The public should not be alarmed, but should be vigilant in protecting themselves from mosquito bites.

New Hanover County Public Health’s Mosquito Control division monitors mosquito activity throughout the county, including coastal areas, and helps control the mosquito population through active surveillance, community education, larviciding to target larvae in breeding environments, and targeted ultra-low volume spraying to kill adult mosquitos based on surveillance data with EPA-registered pesticide approved for public health use in urban environments.

“In addition to this positive sample in trapped mosquitos in New Hanover County, Eastern Equine Encephalitis has also recently been found in a horse in Pender County and one in Brunswick County,” said Public Health Director David Howard. “While human incidence of EEEV is rare, it is a dangerous viral infection that can cause severe disease, so residents should protect themselves by preventing mosquito bites. First and foremost, eliminate all standing water regularly by “tipping and tossing” as only a small amount of water can breed mosquitos, also use EPA approved insect repellent according to labeling instructions. Other options include wearing long sleeves and pants, and limiting outdoor activity at dawn and dusk when mosquitoes are known to be most active.”

To report mosquito activity or concerns, and sign up for spraying alerts, visit PublicHealth.NHCgov.com.

About Eastern Equine Encephalitis (EEE)

EEE virus is only spread to people through the bite of an infected mosquito and cannot be spread from person-to-person, people to animals, or animals to people. Human EEE virus infections occur infrequently, largely because the primary transmission cycle takes place in and around swampy areas where human populations tend to be limited. According to the CDC, people over age 50 and under age 15 seem to be at greatest risk for developing severe disease when infected with the EEE virus; and overall, only about 4-5% of human EEE virus infections result in serious illness. Signs of EEE include the sudden onset of fever, chills, and body and joint aches. Illness can eventually develop into severe encephalitis, resulting in headache, disorientation, tremors, seizures and paralysis. Permanent brain damage, coma and death may also occur in rare cases. There is no approved vaccine or specific antiviral treatment for EEE virus infections.

Preventing mosquito-borne illness

  • Use EPA-registered mosquito repellent that contains DEET (or equivalent) when outside. Use caution when applying to children.
  • If using mosquito treatment on your property, use only as directed on the product label.
  • Reduce time spent outdoors, especially at dawn, dusk and early evening, when mosquitoes are most active.
  • Wear light-colored long pants and long-sleeved shirts.
  • Install or repair screens on windows and doors, and use air conditioning if possible.
  • “Tip and Toss” to reduce mosquito breeding by emptying standing water from flowerpots, gutters, buckets, pool covers, pet water dishes, discarded tires and birdbaths at least twice a week.

Find more mosquito prevention tips and information on the New Hanover County Public Health website and learn more about Eastern Equine Encephalitis on the CDC website.


« Back to news overview

Communications and Outreach: 230 Government Center Drive, Suite 195 • Wilmington, NC 28403 • Phone 910-798-7461 • Fax 910-798-7277
Skip to content