WEST NILE VIRUS
Get the Facts About the West Nile Virus
West Nile virus is a disease spread by mosquitoes. Avoid and prevent the virus with Mosquito Shield. The condition ranges from mild to severe. Below are some basic West Nile Virus facts that will help keep your family healthy.
Mild disease, generally called West Nile fever, has some or all of the following symptoms:
- Abdominal pain
- Back pain
- Lack of appetite
- Muscle aches
- Sore throat
- These symptoms usually last for 3 – 6 days.
With more severe disease, the following symptoms can also occur, and need prompt attention:
- Confusion or change in ability to think clearly
- Loss of consciousness
- Muscle weakness
- Stiff neck
West Nile virus was first identified in 1937 in Uganda in eastern Africa. It was first discovered in the United States in the summer of 1999 in New York. Since then, the virus has spread throughout the United States.
The West Nile virus is a type of virus known as a flavivirus. Researchers believe West Nile virus is spread when a mosquito bites an infected bird and then bites a person.
Mosquitoes carry the highest amounts of virus in the early fall, which is why the rate of the disease increases in late August to early September. The risk of disease decreases as the weather becomes colder and mosquitoes die off.
Although many people are bitten by mosquitoes carrying West Nile virus, most are unaware that they have been exposed. Few people develop severe disease or even notice any symptoms at all.
Mild, flu-like illness is often called West Nile fever. More severe forms of the disease, which can be life-threatening, may be called West Nile encephalitis or West Nile meningitis, depending on what part of the body is affected.
Tests & Diagnosis
Signs of West Nile virus infection are similar to those of other viral infections. There may be no specific findings on a physical examination to diagnose West Nile virus infection.
About 20 – 50% of patients may have a rash. Muscle weakness with other related symptoms are signs of a West Nile virus infection.
Diagnosis is based on the presence of the disease in the locality (any recent travel should be noted to your physician) and the presence of symptoms. West Nile virus or other arboviral disease should be strongly considered when patients over 50 develop unexplained encephalitis or meningitis during mosquito season. Blood tests may confirm the presence of the disease, though prior infections or recent vaccinations can produce false positive results. Some specific testing guidelines can be found at the CDC website. When the disease is extremely serious, a spinal tap or brain imaging may be taken.
West Nile Virus is not caused by bacteria, therefore, antibiotics do not help treat West Nile virus infection. Standard hospital care may help decrease the risk of complications in severe illness.
Research trials are under way to determine whether ribavirin, an antiviral drug used to treat hepatitis C, may be helpful.