Scary because: encephalitis cases occur throughout the US and in many parts of the world, and encephalitis can result in neurological damage and death.

Also scary because the disease can stage outbreaks, such as the current West Nile Virus outbreak in the eastern US.

Symptoms: most infections have no symptoms or mild flu-like symptoms. If encephalitis ensues, however, the victim can suffer paralysis, coma and death.


How you get it: from the bite of an infected insect, usually a mosquito. The insect becomes infected when it bites an animal infected with one of the encephalitis-causing viruses. You do not get it from the animals themselves or from other people.

In the US, mosquito-borne encephalitis takes a small but steady toll every year, occasionally staging small outbreaks. In other parts of the world, particularly Asia, encephalitis is more widespread and outbreaks more common. There is no effective treatment and as yet no vaccine.

Bioterror Special Report