|Videos|December 15, 2016

What is the Prevalence of Powassan Virus in Humans in the US?

Holly Frost, MD, pediatrics physician scientist at the Marshfield Clinic Research Foundation, in Minocqua, Wisconsin, discusses the prevalence of Powassan virus in humans in the United States.

Holly Frost, MD, pediatrics physician scientist at the Marshfield Clinic Research Foundation, in Minocqua, Wisconsin, discusses the prevalence of Powassan virus in humans in the United States.

Interview Transcript (slightly modified for readability)

“This was the first study that looked at the prevalence of Powassan virus in humans. We found that, of patients presenting in the Upper-Midwest with suspected tick-borne disease, about 10% of patients had serologic evidence of Powassan virus.

We also looked at patients who were presenting just for routine chemistry screening, and we found that about 4% of those patients had serologic evidence of a past Powassan virus infection. We know that the prevalence in humans is likely to be higher than what we had previously estimated, because the [virus’s] prevalence in ticks is growing; so, about 7% of Ixodes scapularis ticks in some endemic regions now carry Powassan virus, and up to 90% of mammals in some endemic regions of New England have serologic evidence of Powassan virus.”


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