West Nile Virus Found in NCCo Sentinel Chicken


DNREC officials have found a positive test of West Nile Virus in a sentinel chicken in Southern New Castle County. There have been NO reported cases of West Nile Virus in humans in Delaware so far this year – however the possibility of contracting a mosquito-transmitted disease is possible until colder autumn temperatures arrive – in mid-October or later. You can avoid getting a mosquito-borne illness by avoiding mosquito bites, wearing long-sleeved shirts and long pants, using insect repellent and avoiding peak mosquito activity around dusk, dawn and at night.

Most people infected with WNV do not develop symptoms, but about 20% can develop a mild illness, including fever, body and muscle aches, headache, nausea, vomiting, and rash symptoms. A small number of people can develop serious illness involving neurological problems, paralysis, and possibly death. EEE is not as prevalent as WNV but can present more severe symptoms in humans and horses.

According to the Delaware Department of Agriculture (DDA), there were no equine cases of WNV or EEE in 2021. With the detection of WNV in a sentinel chicken this early in the season, the state veterinarian urges horse owners to contact their veterinarians as soon as possible to vaccinate horses and other equines against WNV and EEE. Both vaccines are highly effective in minimizing disease and may be the reason why Delaware had no equine cases in 2021. Horses that have been vaccinated in the past will need an annual booster shot. Neither disease has a specific drug treatment, and infections in horses are fatal in 70 to 90% of EEE cases and 30% of WNV cases.

  • For requests for mosquito relief in downstate areas south of Dover, contact Mosquito Control’s Milford field office at 302-422-1512.
  • For animal health questions, contact the Delaware Department of Agriculture’s Poultry and Animal Health section at 302-698-4500.
  • To report suspected cases of human WNV, call the Division of Public Health Office of Infectious Disease Epidemiology toll-free at 888-295-5156.
  • For more information on West Nile virus or Eastern equine encephalitis, visit www.cdc.gov/ncidod/dvbid/westnile/index.htm