|Videos|November 1, 2016

What is Powassan Virus?

Holly Frost, MD, pediatrics physician scientist at the Marshfield Clinic Research Foundation, in Minocqua, Wisconsin, explains what Powassan virus is.

Holly Frost, MD, pediatrics physician scientist at the Marshfield Clinic Research Foundation, in Minocqua, Wisconsin, explains what Powassan virus is.

Interview Transcript (slightly modified for readability)

“Powassan virus is a tick-borne flavivirus that was first discovered in Ontario in 1956. Powassan virus is known to be carried by the Ixodes scapularis, or the black-leg tick, which is also known as the deer tick. That’s the same vector that carries Lyme disease, Anaplasma, and Babesia.

It’s a relatively newly discovered virus, and so we don’t know exactly how prevalent it is in humans in the United States, but we do know that about 7% of ticks in endemic areas for Lyme disease also carry Powassan virus, and that in, some mammal populations in the Northeast, up to 90% of the population can have Powassan virus.”


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