Health officials in Maine are reporting two confirmed cases of the tickborne disease, Powassan virus, in midcoast residents. The Maine Center for Disease Control and Prevention (Maine CDC) said Wednesday that it was notified of the two cases last week.


The two adults became ill in late April and were hospitalized with encephalitis, or inflammation of the brain, caused by the virus. Both have since been discharged.

The cases were confirmed by the Centers for Disease Control and Prevention’s (CDC) lab in Fort Collins, CO.

Maine has seen nine Powassan virus cases since 2000. The CDC says from 2006 through 2015, approximately 75 cases, or an average of 7 cases were reported annually nationally. Most cases have occurred in the Northeast and Great Lakes region.

LISTEN: Powassan virus: A discussion with Durland Fish, PhD

Signs and symptoms of Powassan infection can include fever, headache, vomiting, weakness, confusion, seizures, and memory loss. Long-term neurologic problems may occur. Long-term sequelae occurs in approximately 50% of patients. Approximately 10-15% of cases are fatal.

Related: Tickborne diseases: It’s not just Lyme disease

Reducing exposure to ticks is the best defense against Powassan virus disease, Lyme disease, Rocky Mountain spotted fever, and other tickborne infections.