Powassan Virus Surges to Record U.S. Cases, Spreading Fast After Tick Bites

A rare tick-borne virus called Powassan has reached a record number of U.S. cases (76 in 2025). The virus can be transmitted by ticks in as little as 15 minutes, can progress to severe neurological illness, and there are no vaccines or specific treatments—only supportive care. Most at risk are children, older adults, and immunocompromised individuals, making prevention through tick avoidance essential.