Encephalitis is defined as inflammation of the brain. This definition means encephalitis is different from meningitis, which is defined as inflammation of the layers of tissue, or membranes, covering the brain. Encephalitis is a rare condition and occurs most often in the first year of life and decreases with age. The major causes of encephalitis are viral infections where the virus is transmitted by breathing in respiratory droplets from an infected person,contaminated food or drinks,mosquitoes and other insects.
Some patients may have symptoms of cold or stomach infection but when the infection is severe the symptoms may include:
Diagnosis and Treatment
Blood and urine tests that may be helpful include the following:
A lumbar puncture (LP) should be performed in all cases of suspected viral encephalitis. Cases of encephalitis due to certain viruses usually require intravenous antiviral treatments. Antiviral drugs commonly used to treat encephalitis include: • Acyclovir (Zovirax) • Ganciclovir (Cytovene) • Foscarnet (Foscavir)
Determining the true incidence of encephalitis is impossible, because reporting policies are neither standardized nor rigorously enforced. The arbovirus group is the most common cause of episodic encephalitis, with a reported incidence. Individuals at the extremes of age are at highest risk, particularly for HSE.