DOVER, DE (Aug. 31, 2022) – The Division of Public Health (DPH) is announcing this year’s first human case of West Nile Virus (WNV), in a 78-year-old Sussex County man. West Nile Virus is a mosquito-borne illness that can cause serious health problems.   

In addition to the first human WNV case, there also have been confirmed cases in a horse in New Castle County, and in 19 sentinel chickens in outdoor-caged and humanely tended stations maintained throughout the state by the Department of Natural Resources and Environmental Control (DNREC).  Delawareans should be aware that mosquitoes that cause WNV bite primarily during the evening and morning hours; or dusk and dawn. However, mosquitoes that cause other diseases such as chikungunya, dengue fever, and Zika can bite during the day. It is important to protect yourself by wearing insect repellent whenever you go outdoors. 

WNV is transmitted by mosquitoes, generally in summer and fall, with a peak period for disease transmission from mid-August to mid-October. Nearly 80 percent of people infected with WNV will not become ill. Less than 20 percent of those infected with the virus will develop mild symptoms such as fever, headache, body aches, a skin rash on the chest or back, and swollen lymph glands. Approximately one in 150 people infected will develop severe infection which may include headache, high fever, stiff neck, tremors or convulsions, muscle weakness, encephalitis or meningitis, all possibly leading to hospitalization and very rarely death. The elderly and those with weakened immune systems are most at risk to contract WNV from mosquitoes. Anyone who experiences any of these severe symptoms should immediately seek medical assistance.  

To avoid mosquito bites and reduce the risk of infection, individuals should: 

• Use Environmental Protection Agency (EPA)-registered insect repellents. Follow the manufacturer’s instructions for reapplication times. 
• If using sunscreen, apply it first and insect repellent second. 
• Adults taking precaution with children against biting mosquitoes should spray insect repellent onto their hands and then apply it to the child’s face. Do not apply insect repellent onto a child’s hands, eyes, mouth, or on cuts or irritated skin. 
• Do not use insect repellent on babies younger than two months of age. 
• When outside during periods of mosquito activity, wear light-colored long-sleeved shirts and long pants. 
• Dress children in clothing that covers arms and legs. 
• Consider using mosquito netting, which offers protection to the face and neck and also protects infants in carriages, strollers and playpens.

• Use permethrin (an insecticide) to treat clothing and gear (such as boots, pants, socks, and tents), but do not apply to the skin. 
• Prevent mosquitoes from entering the house by using screens and tightly sealed windows and doorways.  

DNREC’s Mosquito Control section announced WNV in sentinel chickens for the first time in July 2021. Mosquito-transmitted virus detections in DNREC’s sentinel chickens are unrelated to Delaware’s poultry industry. The possibility of contracting mosquito-transmitted diseases, including WNV and Eastern Equine Encephalitis (EEE), will continue until colder autumn temperatures in mid-October or later.  

• To report suspected cases of human WNV, call the DPH Office of Infectious Disease Epidemiology at 1-888-295-5156. 
• For more information about mosquitoes and mosquito-borne illnesses, use the following resources: 

• • For mosquito biology/ecology and control, contact the DNREC Mosquito Control section office in Dover at 302-739-9917. 
  • For requests for mosquito relief in upstate areas from Dover north, contact Mosquito Control’s Glasgow field office at 302-836-2555. 
  • For requests for mosquito relief in downstate areas south of Dover, contact Mosquito Control’s Milford field office at 302-422-1512. 
• Contact the Delaware Department of Agriculture’s Poultry and Animal Health Section for animal health questions at 302-698-4500. 
• To report suspected cases of human WNV, call the DPH Office of Infectious Disease Epidemiology toll-free at 1-888-295-5156. 

For more information on West Nile Virus or Eastern Equine Encephalitis, visit https://dhss.delaware.gov/dhss/dph/epi/wnv.html.

For more information on what you can do to prevent West Nile Virus, visit the Centers For Disease Control and Prevention’s website, www.cdc.gov/westnile/prevention/index.html.

###

The Delaware Division of Public Health (DPH), a division of the Delaware Department of Health and Social Services, is a nationally accredited public health agency recognized by the Public Health Accreditation Board for its outstanding dedication to driving change through innovation. DPH is committed to improving the quality of the lives of Delaware’s citizens by promoting health and well-being, fostering self-sufficiency, and protecting vulnerable populations. 

Anyone who is deaf, hard of hearing, Deaf-Blind, or speech-disabled can contact DPH by first dialing 711 using specialized devices (i.e., TTY, TeleBraille, voice devices). The 711 service is free; to learn more about how it works, visit delawarerelay.com.

About DNREC

The Delaware Department of Natural Resources and Environmental Control protects and manages the state’s natural resources, protects public health, provides outdoor recreational opportunities, and educates Delawareans about the environment. The DNREC Division of Fish and Wildlife conserves and manages Delaware’s fish and wildlife and their habitats, and provides fishing, hunting, wildlife viewing and boating access on nearly 68,000 acres of public land. For more information, visit the website and connect with @DelawareDNREC on Facebook, Twitter or LinkedIn.  

Media contacts: Michael Globetti, michael.globetti@delaware.gov; Joanna Wilson, joanna.wilson@delaware.gov

Print