Viral Encephalitis By: Alan Gooden
What is Viral Encephalitis? Encephalitis literally means “inflammation of the brain” but it usually results from a viral infection. Encephalitis occurs in two forms — a primary form and a secondary form. Primary encephalitis involves direct viral infection of your brain and spinal cord. In secondary encephalitis, a viral infection first occurs somewhere in your body and then travels to your brain.
Causes Usually a result of viral infections passed between humans, or from contact with infected animals or insects. Viruses that cause this include the West Nile virus, herpes viruses, and rabies. It can develop 5 to 10 days after a childhood illness such as chickenpox, measles, mumps, polio, etc or, on rare occasions, occur weeks, months, or years after the initial viral infection.
Symptoms fever, headache, sensitivity to light, confusion, decreased level of consciousness Most people only have mild, often flu-like symptoms. In some cases, people might not have any symptoms. More serious infections can cause: hallucinations, personality changes, double vision, muscle weakness, and seizures. In infants, the bulging of the fontanels is the main symptom of viral encephalitis.
Area of Nervous System Affected It can arise in the brain and directly attack the brain and spinal cord. The virus can travel to the nervous system after beginning somewhere else in the body.
Who is affected? Older people and younger children are at a greater risk of serious disease and death from West Nile and St. Louis encephalitis. California encephalitis poses a greater danger to children under 15 years of age. Having a weakened immune system puts you at risk for many types of encephalitis.
Prognosis Episodes last about one to three weeks, with fever and symptoms that gradually or suddenly subside. However, it may take months for you to fully recover.
Treatment Encephalitis requires immediate emergency care so that diagnosis and treatment can begin as soon as possible. Plenty of rest, liquids, and Tylenol are used to treat mild cases. More serious cases call for the use of anti-viral and anti-inflammatory drugs.
Resources http://www.pdrhealth.com/disease/disease-mono.aspx?contentFileName=BHG01ID01.xml&contentName=Viral+Encephalitis&contentId=159§ionMonograph=ht1 http://www.mayoclinic.com/health/encephalitis/DS00226
Other Info The most common insect-borne encephalitis in the U.S. is St. Louis encephalitis. The St. Louis encephalitis virus is transmitted by mosquitoes which bite humans thus causing West Nile. The Herpes Virus is the main cause of many encephalitis cases.