West Nile Virus


West Nile Virus is transmitted to humans by mosquitoes. West Nile virus was discovered in the West Nile district of Uganda in the year 1937 and hence the name. West Nile Virus infected person usually do not fall ill but in rare cases it can lead to fatal infection of brain, spinal cord or nerves like encephalitis or meningitis. The mosquitoes get the infectious West Nile Virus from birds when they bite the birds. Birds acts as host to West Nile Virus and develop the virus to infectious level. Once the mosquito bites the infected bird, it becomes a transmitting vector of the West Nile Virus. The West Nile Virus created news in 1999 when it appeared for the first time in United States affecting residents of New York City. Older people and people with low immune system are more prone to be infected with West Nile Virus.

Causes of disease

West Nile Virus is passed on to humans by mosquito bites. Mosquitoes become vectors of West Nile Virus by biting birds that carries the virus. In no way the virus is passed on to humans by human-to-human contact or by birds directly. The transmission happens only through mosquito bite. However, in few rare cases, the virus can be transmitted by following ways, other than mosquito bites:

  • Transfusion of blood to a person from one who is infected with West Nile Virus.
  • Organ transplant when the person donating the organ is infected with West Nile Virus
  • From a mother to an unborn child during pregnancy.
  • To a child while breastfeeding in case the mother is infected with West Nile Virus.

Symptoms and Signs

West Nile Virus infection in most of cases does not present any specific symptoms. However, in some cases people infected with West Nile Virus can have West Nile fever with following symptoms:

  • Mild to high fever and vomiting
  • Head Ache and body ache
  • Swollen Lymph Glands.
  • Skin Rashes

However, in few rare cases West Nile Virus can cause serious complication by affecting brain, spinal cord and nervous systems of the infected person. In such complications, the following symptoms are noticed:

  • Muscle weakness
  • High fever (Sometimes with shivering)
  • Loss of eyesight
  • Severe headaches
  • Numbness
  • Stiff neck and joint aches
  • Confusion or unstable mental status

In case a person has been bitten by mosquito and have the above mentioned symptoms then he or she should immediately consult a doctor.

Treatment of disease

Diagnosis of West Nile Virus infection is done based on study of symptoms presented and molecular biologic tests. Generally people with mild symptoms are not suggested further tests. Only person with severe symptoms are asked to undergo further tests in specialized laboratories. There is no specific treatment or approved shots for West Nile Virus infection. People with mild symptoms take medication for fever and aches and gets better without any specific treatment.  People with severe symptoms may have to go to a hospital and get prescribed medication for treating the symptoms presented. People with severe symptoms may be asked to get hospitalized and are kept under medical supervision. It is always better to consult a doctor and seek medical guidance in case you have developed any of the symptoms as described above.

Prevention of disease

The following are the ways for prevention against West Nile Virus infection

  • Avoid contact with mosquitoes.
  • Use mosquito repellents and bug sprays in your house (However, make sure to keep the mosquito repellent and bug sprays away from children).
  • Wear protective clothing (like long sleeve shorts, full trousers etc) when visiting outside during dawn or evening.
  • Put netted screens on your windows and doors to avoid mosquitoes from entering inside your house
  • Get rid of mosquito breeding grounds like stagnant water, open drains, water cans etc.
  • Maintain cleanliness and hygienic lifestyle.