Encephalitis is an inflammation of the brain. The most common cause is a virus, but it can also be caused by bacteria and fungi. The condition is called primary encephalitis if the virus attacks the brain directly, and secondary if the virus first attacked another part of the body and spread to the brain. The virus can also attack the spinal cord and the meninges. Meninges are the membranes that enclose the brain.Encephalitis strikes both sexes and can happen at any age, but it most often attacks the very old, the very young and people with weakened immune systems. People who live in areas that are heavily infested by mosquitoes are also at higher risk. Enccephalitis can be caused by different viruses, and in the United States the most common virus that causes the disease is the herpes simplex virus. People can also get the disease through arboviruses spread through ticks and mosquitoes. The viruses that cause measles, mumps and chickenpox can also be causes of encephalitis. In extremely rare cases, the virus that causes rabies can lead to the disease.Clearly, encephalitis can be a dangerous disease, but deaths and complications such as coma and brain damage are rare. Diagnostic tools include imaging tests such as CT and MRI scans and tests of blood and spinal fluid. In some cases, the doctor will perform a brain biopsy, which takes a small piece of the patient’s brain and has it studied under a microscope.
Most people with encephalitis need to be hospitalized though a patient with a mild case may be asymptomatic or have such mild symptoms that they do not take notice of them. For other patients, their symptoms last three to five days. Otherwise healthy people who get encephalitis usually recover completely, but this can take some months.
Most people with encephalitis need to be hospitalized though a patient with a mild case may be asymptomatic or have such mild symptoms that they do not take notice of them. For other patients, their symptoms last three to five days. Otherwise healthy people who get encephalitis usually recover completely, but this can take some months.