Is encephalitis contagious?

Whether encephalitis is contagious depends on its specific type. Common types include epidemic Japanese encephalitis, tuberculous meningitis, and autoimmune encephalitis.

1. Epidemic Japanese Encephalitis

If a mosquito bites a person infected with epidemic Japanese encephalitis and then bites a healthy individual, it may transmit the virus to that person. Similarly, if a mosquito first bites an infected pig carrying the Japanese encephalitis virus and subsequently bites a human, transmission to the human may also occur.

2. Tuberculous Meningitis

Tuberculous meningitis can be transmitted via saliva and potentially through airborne routes. Kissing an infected person or sharing a poorly ventilated, enclosed space with them may result in airborne transmission of the causative bacteria to others.

3. Autoimmune Encephalitis

Autoimmune encephalitis is an autoimmune disorder in which the body’s immune system mistakenly attacks its own healthy brain tissue—recognizing normal neural structures as abnormal—and thereby causes damage. However, this condition is not contagious and cannot be transmitted to others.