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The West Nile Virus (WNV) is contracted through the bite of an infected mosquito and can be a potentially serious illness that affects the central nervous system. However, about 80% of all those who contract WNV will not have any symptoms at all, never knowing they were infected.
Roughly 20% who contract WNV will develop West Nile Fever (WNF). The symptoms of WNF are fever, headache, body aches, possible vomiting, tiredness, swollen lymph glands, and occasionally, a rash on the stomach or back.
There is no specific treatment for West Nile Virus, and symptoms will subside on their own. Over-the-counter medication to relieve headaches and body aches may provide relief. Symptoms normally last a few days, but can last several weeks, even in healthy people. WNF has no lasting harmful effects.
The real concern over WNV has to do with the slightly-less-than-1% of those infected, who will develop severe neuroinvasive disease. These WNV severe diseases are:
- West Nile encephalitis (inflammation of the brain)
- West Nile meningitis (inflammation of the membrane around the brain and the spinal cord)
- West Nile poliomyelitis (inflammation of the spinal cord)
Symptoms of severe disease may include high fever, headaches, convulsions, muscle weakness, stiff neck, stupor, confusion, numbness and paralysis. In the case of severe disease, the symptoms can last several weeks and may result in permanent neurological damage.
It is possible to experience brief WNF-like symptoms before developing severe disease, but the Center for Disease Control (CDC) does not know the percentage of people in which this occurs.
There is no treatment for West Nile Virus severe disease; however, hospitalization is necessary to provide care as needed. This might include IV fluids, respiratory aid, or preventative measures against secondary infections.
West Nile Virus cannot be spread by a hug, a touch, or even kissing, however a small number of cases have reported the spread through breastfeeding and during pregnancy, from mother to child.
The best way to avoid West Nile Virus is to avoid mosquitoes. Mosquitoes are most active at dawn and dusk. If there are mosquitoes in your area and you must be outside, use an insect repellent containing DEET. Mosquitoes are attracted to dark clothing; if you wear light clothing you'll not only attract fewer mosquitoes but you'll be able to see them on your clothes. Make sure the screens on your windows and doors are secure, and don't allow standing water to collect in your yard, as this provides a breeding ground for mosquitoes.
Mosquitoes contract West Nile Virus through feeding on infected birds. If you see a dead bird do not use your bare hands to remove it. Contact your local health department for instructions on disposal of the body.
The CDC notes that milder cases of West Nile Virus will improve on their own, and in these cases medical attention is unnecessary. However, if you suspect you might have WNV, even in a mild form, seeing a doctor is always a good precaution to take. If your symptoms are harsher, for example a severe headache or confusion, see your doctor immediately.