Overview of encephalitis
Encephalitis is often classified as a viral disease that causes inflammation and swelling in the brain. In some cases it can be an abnormal functioning of the body’s immune system where the antibodies start attacking the cells and tissues of the brain and spinal cord.
Causes of encephalitis
In most cases a virus is the main cause of encephalitis. The genus of virus called flavivirus is the chief cause of encephalitis. This group of virus has several strains that include yellow fever virus (YFV), West Nile virus (WNV), Japanese encephalitis virus (JEV), Saint Louis encephalitis virus (SLEV), and dengue viruses. Flavivirus is generally transmitted through mosquitoes and ticks and mostly has severe affects on children and the elderly. In some cases the encephalitis maybe caused due to consuming food or water that has been infected by enteroviruses. Example of enteroviruses is group A coxsackievirus, which is known the infect children. Another known cause of encephalitis virus is the herpes virus. This virus is known to cause diseases like chickenpox but in some cases can cause encephalitis. Other viruses include the Herpes Simplex Virus, Varicella-Zoster Virus, Epstein - Barr virus amongst others.
Symptoms for encephalitis include:
- Sensitivity to light or sound
- Poor memory/memory loss
- Weakness or numbness of arm or leg
In the case of encephalitis, a symptom alone is not enough to ascertain the disease. Similar symptoms can exist for other diseases and hence becomes very important to run tests to confirm the illness. According to the Encephalitis Society, UK tests which can help confirm the diagnosis and rule out other disorders include:
Imaging tests such as computerized tomography (CT) and magnetic resonance imaging (MRI) are at the forefront of diagnosis. Computerized Tomography (CT) or Magnetic Resonance Imaging (MRI) scans may show the extent of the inflammation in the brain and help differentiate encephalitis from other conditions. Brain scans can exclude stroke, brain tumors and brain aneurysms.
There is, however, limitations to imaging tests as encephalitis in the early stages may not be detected thorough such tests. Another test called Electroencephalogram (EEG), which records brain waves, can detect abnormal patterns of activity. These abnormal patterns can be lax and sluggish brain activity as well as epileptic seizures, says Encephalitis Society.
Encephalitis if untreated can be a fatal disease and cause irrevocable damage to the brain. When encephalitis is suspected the patient is first normally treated with an antiviral medicine called acyclovir.
Prevention for encephalitis revolves around practicing good health and hygiene standards. It is also important to prevent mosquito bites and use mosquito repellent and insecticides. Eliminate standing water and prevent mosquitoes from breeding. Yong children should be protected by mosquito bites and as far as possible their skin should be covered.
Written by: Healthplus24 team
Date last updated: August 19, 2013