West Nile Virus

1 What is West Nile Virus?

West Nile infections is a mosquito transmitted disease which produces mild to no symptoms.

However, some people may develop severe complications of the disease like meningitis among others.

Protecting oneself from mosquitos may help to prevent this disease.

People with this disease recover on their own but life threatening symptoms may require immediate care.

2 Symptoms

Less than half of the people infected with West Nile virus develop mild signs and symptoms which include:

In a small number of people, the virus may cause serious neurological infections like encephalitis (inflammation of brain) or meningitis (inflammation of meninges).

The signs and symptoms of severe infection includes:

  • high fever,
  • severe headache,
  • stiff neck,
  • disorientation,
  • mental confusion,
  • stupor or coma,
  • tremors or muscle jerking,
  • seizures
  • partial paralysis.

The mild form of this disease usually lasts for about a week but that of neurological infections can linger for months.

Some symptoms like muscle weakness may become permanent.

3 Causes

A bite by an infected mosquito is the main cause of West Nile virus. Mosquitos get infected when they feed on infected birds.

It does not spread by casual contact between humans or animals. Most people get this disease warm weather when the mosquitos are most active.

This disease mostly occurs in Africa, Asia, Europe, and the Middle East.

Only Alaska and Canada are such places where there have no cases of this disease.

There are a few cases where this disease is spread through:

  • organ transplantation,
  • placenta (spread to child from mother during pregnancy),
  • blood transfusion
  • breast feeding.

4 Making a Diagnosis

The doctor will diagnose West Nile virus by:

  • some physical examination,
  • complete assessment of the patient’s medical history,
  • some tests.

The tests include:

  • Blood tests - A high level of specific antibodies to the West Nile virus can testify to the diagnosis.
  • Lumbar Puncture - this tests includes taking a sample of cerebrospinal fluid from the spinal cord and its analysis.
  • Brain tests - in rare cases, an electroencephalography may be required to measure the electrical activity of the brain and assess its function.  

5 Treatment

Many people with mild form of West Nile virus recover without treatment but in most severe cases certain procedures and medications are required.

Over-the counter pain relievers or non-steroidal anti-inflammatory drugs may help to ease the symptoms for mild cases.

Attention should be paid while giving aspirin. A new kind of procedure called the Interferon therapy in which the immune cells called interferons are used against the virus for the treatment of encephalitis and meningitis caused by West Nile virus.

6 Prevention

Prevention is better than cure and thus following are the ways by which West Nile disease can be prevented:

  • unclog roof gutters,
  • empty unused swimming pools or other standing water,
  • change water in the birdbaths,
  • remove old tires or unused containers that might hold water and let the mosquitoes breed,
  • repair windows and doors,
  • avoid unnecessary outdoor activity especially in evening,
  • wearing clothes that cover the body completely
  • apply mosquito repellant when possible.

7 Risks and Complications

There are several risks and complications associated with West Nile virus.

Quite often, this infection occurs from June till September.

The following are the factors that increases the risk of having severe infection:

  • Age - being old increases the risk.
  • Certain diseases - having diseases like cancer, diabetes, hypertension and kidney disease may increase the risk two-fold.

Complications of the serious infection includes:

  • partial or total paralysis,
  • coma
  • even death.

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