Powassan (POW) virus is a flavivirus and currently the only well documented tick-borne transmitted arbovirus occurring in the United States and Canada. Powassan encephalitis is a serious illness caused by the Powassan virus. This virus was first recognized in the small town of Powassan, Ontario in 1958. Due to the ability of the virus to cause encephalitis, it was and still is considered a very serious tick-borne illness.
Powassan encephalitis can cause residual neurological problems in patient who recover. Powassan in not common in humans, but Maine has seen a few human cases in last decade. Powassan can be carried by the deer tick (Ixodes scapularis).
On this page:
- Powassan Fact Sheet (PDF)
- Tickborne Disease Webinar
- Frequently Asked Tick Questions
- Tick Identification