A tick virus now surging in New England can be traced back to an Ontario 4-year-old's death in 1958

Key Points:

• Powassan virus, a tick-borne illness first identified in 1958, is increasingly diagnosed in the northeastern United States, with a record 76 cases reported in 2025, primarily in New England and the Upper Midwest.
• The virus is spread by blacklegged ticks, which are more likely to bite humans and can transmit the virus rapidly, often causing severe neurological symptoms and a 10-15% fatality rate in symptomatic cases.
• The rise in Powassan virus cases is part of a broader increase in tick-borne diseases linked to factors such as growing deer populations, suburban development, and warmer winters that extend tick activity.
• Personal prevention remains the best defense, including tick identification, regular full-body checks, prompt tick removal, and use of permethrin-treated clothing, while states explore measures like deer management and vaccine development.
• Despite ongoing efforts, Powassan virus remains difficult to diagnose and control, underscoring the importance of awareness and prevention without discouraging outdoor activity.