West Nile Virus Questions and answers

What are symptoms of West Nile Virus 
Infection with West Nile Virus can be occur without symptoms or can lead to West Nile Fever or severe West Nile disease.

West Nile Fever
It is estimated that around 20% of people who become infected with West Nile Virus develop West Nile Fever. Symptoms include fever, headache, fatigue, body aches – occasionally with a skin rash on the torso – and swollen lymph glands. While the illness may last no longer than a few days, even healthy people have reported being sick for several weeks.

Severe West Nile Disease
Symptoms of severe West Nile Disease (also called neuroinvasive disease, such as West Nile encephalitis or meningitis or West Nile poliomyelitis) include headache, high fever, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness and paralysis. It is estimated around 1 in 150 persons infected with West Nile Virus will develop a more severe form of the disease. Serious illness can occur in people of any age. Most at risk, however, are those over 50 and some persons with suppressed immune systems such as transplant patients.

Most people (4 out of 5) who are infected with West Nile Virus will not develop any type of illness. However, you cannot know ahead of time if you will get sick or not if infected.

Incubation time
It usually takes two to 15 days for symptoms to appear after exposure to the infection.

How long symptoms last
Symptoms of West Nile Fever generally last a few days, although even some healthy people have had the illness last for several weeks. Symptoms of Severe West Nile Disease, such as encephalitis or meningitis, may last several weeks, and neurological effects may be permanent.

Differences between types of West Nile illnesses
Neuroinvasive disease, which affects the nervous system, is the most severe form of disease from West Nile virus infection. Specific types of neuroinvasive disease include West Nile encephalitis, West Nile meningitis, West Nile meningoencephalitis and West Nile poliomyelitis.   Encephalitis refers to an inflammation of the brain; meningitis is an inflammation of the membrane around the brain and the spinal cord; meningoencephalitis refers to inflammation of the brain and the membrane surrounding it and poliomyelitis refers to an inflammation of the spinal cord.
West Nile Fever is another type of illness that can occur in people who become infected with the virus. It is characterized by fever, headache, fatigue, aches and sometimes rash.

Can West Nile Fever turn into West Nile encephalitis
When someone is infected with West Nile Virus, they will typically have one of three outcomes: No symptoms (most likely); West Nile Fever (in 20 percent of people) or Severe West Nile Disease, such as meningitis or encephalitis (less than 1% of those who get infected). If you develop a high fever with severe headache, consult your healthcare provider.

West Nile Fever does not appear to cause permanent health effects. There is no specific treatment for West Nile Virus infection. People with West Nile Fever recover on their own, although symptoms can be relieved through various treatments.

Some people may develop a brief, West Nile Fever-like illness before they develop more severe disease. Occasionally, an infected person may develop more severe disease such as West Nile encephalitis or West Nile meningoencephalitis. Although there is no treatment for West Nile Virus infection itself, the person with severe disease often needs to be hospitalized. Care may involve administration of IV fluids, respiratory support and prevention of secondary infections.