Summer Encephalitis

Summer Encephalitis
Summer Encephalitis

Overview Of Summer Encephalitis

Summer Encephalitis is synonymous with the term West Nile Virus. West Nile Virus is a disease spread by mosquitoes. The condition ranges from mild to severe.

Commonly Associated With

Encephalitis – West Nile; Meningitis – West Nile

Causes Of Summer Encephalitis

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 US.

Researchers believe summer encephalitis is spread when a mosquito bites an infected bird and then bites a person.

Mosquitoes carry the highest amounts of the virus in the early fall, which is why more people get the disease in late August to early September. As the weather becomes colder and mosquitoes die off, there are fewer cases of the disease.

Although many people are bitten by mosquitoes that carry West Nile virus, most do not know they have been infected.

Risk factors for developing a more severe form of West Nile virus include:

  • Conditions that weaken the immune system, such as HIV/AIDS, organ transplants, and recent chemotherapy
  • Older or very young age
  • Pregnancy
  • West Nile virus may also be spread through blood transfusions and organ transplants. It is possible for an infected mother to spread the virus to her child through breast milk.

Symptoms Of Summer Encephalitis

Symptoms may occur 1 to 14 days after becoming infected.

Mild disease, generally called West Nile fever, may cause some or all of the following symptoms:

  • Abdominal pain
  • Fever, headache, and sore throat
  • Lack of appetite
  • Muscle aches
  • Nausea, vomiting, and diarrhea
  • Rash
  • Swollen lymph nodes
  • These symptoms usually last for 3 to 6 days but may last a month.

More severe forms ofsummer encephalitis are called West Nile encephalitis or West Nile meningitis, depending on what part of the body is affected.

The following symptoms can occur, and need prompt attention:

  • Confusion or change in ability to think clearly
  • Loss of consciousness or coma
  • Muscle weakness
  • Stiff neck
  • Weakness of one arm or leg

Exams & Tests

Signs ofsummer encephalitis infection are similar to those of other viral infections. There may be no specific findings on a physical examination. About one-half of people with West Nile virus infection may have a rash.

Tests to diagnose West Nile virus include:

  • Blood test or a spinal tap to check for antibodies against the virus
  • Head CT scan
  • Head MRI scan

Treatment Of Summer Encephalitis

Because this illness is not caused by bacteria, antibiotics do not treat West Nile virus infection. Supportive care may help decrease the risk of developing complications in severe illness.