What is the West Nile virus?
West Nile virus belongs to the group of Japanese encephalitis and most of the time it causes a viral flu-like disease.
Why is it named like this?
This virus took its name from the fact that it was detected for the first time in a febrile woman in Uganda, West Nile province.
How is it transmitted?
West Nile virus is mainly transmitted through an infected mosquito bite.
Less common ways of transmission are: through blood transfusion and organ transplantation, while sporadic cases of transmission from the mother to the fetus during pregnancy, through breast feeding and through sick birds handling have been reported.
Which are the symptoms?
In 80% of the infections, the disease runs subclinically without any symptom. In approxiamtely 20% of the cases, the patient develops "West Nile fever", which is a flu-like disease with fever, headache, pain in the joints and muscles, rash and lymph nodes enlargement. In less than 1% of the cases, a severe form of the disease may take place with meningitis/encephalitis (high fever, behaviour changes) or even coma and death.
How quickly do the symptoms appear?
From the time the infected mosquito bites the person until the time the person develops symptoms of the disease is usually 2-14 days - a period that may be prolonged in case of immunocompromise.
For how long do the symptoms last?
The symptoms of the mild form of the disease last 5-7 days, except for cases of immune system disorders that may be a cause of prolongation.
Who is in greater risk of West Nile virus disease?
The most sensitive and vulnerable population groups are the immunosuppressed and the elders (with underlying diseases).
Is there an appropriate treatment for West Nile virus?
There is no specific treatment for West Nile virus, but in case of severe disease, supporting measures are impemented in the hospital.
Is there a vaccine for West Nile virus?
Until now, there is not a human vaccine available, although many research projects towards this direction are in progress.
What can I do in order to be protected from mosquito bites?
You should avoid staying outdoors during peak hours of mosquito activity, ie from dusk till dawn and when inevitable, you should use insect repellents.
As for protection measures in the house, you should use window/door screens, insecticides and insect repellents. In addition, you should eliminate any source of standing water that may favour the proliferation of mosquitoes.