Encephalitis literally means an inflammation of the brain, but it usually refers to brain inflammation caused by a virus. It may also be called “acute viral encephalitis or aseptic encephalitis”. Encephalitis is an infectious disease of the Central Nervous System characterized by pathologic changes in both the gray and white matter of the spinal cord and brain. It may be due to specific disease entity such as rabies or an arthropod-borne virus (arbovirus), or it may occur as a sequela of influenza, measles, German measles, chicken pox, herpes virus infection, small pox, vaccinia, or other diseases. The specific viruses involved may vary. Exposure can also occur through insect bites, food or drink, or skin contact.
Once the virus has entered the blood stream, it can localize the brain causing inflammation of brain cells and surrounding measures. White blood cells invade the brain tissue as they try to fight off the infection. The brain tissue swells (cerebral edema) and can cause destruction of nerve cells, bleeding with in the brain (intracerebral hemorrhage), and brain damage. This can cause neurologic deficits such as parplysis, speech changes, increased intracranial pressure, respiratory failure, seizure disorders, and shock can occur.
SIGNS AND SYMPTOMS
Mild cases absent superficial reflexes Sudden fever ***exaggerated deep tendon reflexes
Loss of energynuchal rigidity
General sick feelingincreases resp. tract problems
High feversore throat
Severe HA ***malaise
N/V ***muscle stiffness
Stiff neck ***photophobia
Pupils of different sizesvisual disturbances
Disorientationspastic or flaccid paralysis
Problems in speech or hearinglethargy