By Capt. Heather Ferguson, Entomologist, U.S. Army Public Health CommandAugust 1, 2013
West Nile virus is commonly found throughout the United States as well as Africa, West Asia and the Middle East. WNV took a serious health toll nationally last year, causing more than 5,000 illnesses and 243 deaths. In the Maryland, District of Columbia and Virginia region, there were 75 illnesses and 9 deaths; the second highest number of cases since WNV appeared in the States back in 1999. WNV is spread by the bite of an infected mosquito and can infect people, horses, many types of birds and some other animals.
Preventing mosquito bites is the best way to avoid becoming infected with the West Nile virus.
To reduce exposure to West Nile virus:
•Use an approved insect repellent every time you go outside and follow the instructions on the label. Among the EPA-approved repellents are those that contain DEET, picaridin or oil of lemon eucalyptus.
•Regularly drain standing water--including water collecting in empty cans, tires, buckets, clogged rain gutters and saucers under potted plants. Mosquitoes that spread WNV breed in stagnant water.
•Wear long sleeves and pants at dawn and dusk when mosquitoes are most active.
•Use air conditioning or make sure there are screens on all doors and windows to keep mosquitoes from entering the home.
There is no evidence that West Nile virus can be spread from person to person or from animal to person.
Symptoms of the milder form of illness, West Nile fever, can include headache, fever, muscle and joint aches, nausea and fatigue. People with West Nile fever typically recover on their own, although symptoms may last for several weeks. Symptoms of the more serious form, West Nile neuroinvasive disease, can include those of West Nile fever plus neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness and paralysis. Up to 80 percent of people infected with the virus will have no symptoms.
There are no medications to treat or vaccines to prevent West Nile virus infection for people. Those individuals over 50 years old and those with other health issues are at a higher risk of becoming seriously ill or dying when they become infected with the virus. If people have symptoms and suspect West Nile virus infection, they should contact their healthcare provider.