#2: Another Tick-Borne Disease Growing in the United States: Powassan Virus
In October 2016, at the Infectious Disease Society of America annual meeting, ID Week 2016, held in New Orleans, Louisiana, Contagion®
interviewed Holly Frost, MD, pediatrics physician scientist at the Marshfield Clinic Research Foundation, in Minocqua, Wisconsin, on an emerging infectious disease, Powassan virus.
Powassan virus, she said, is a “tick-borne flavivirus that was first discovered in Ontario in 1956.” This virus can be transmitted through the bite of Ixodes scapularis
, also known as the black-leg tick or the deer tick. This tick can also transmit Lyme disease, which may or may not cause chronic Lyme disease
Because this tick-borne infection is relatively new, said Dr. Frost, researchers are still not 100% sure of on incidence of infection in humans in the United States, until now.
Discussing her research team’s study, which was presented during ID Week 2016, Dr. Frost said during her interview, “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."
According to her findings, approximately 7% of Ixodes scapularis
ticks in some US regions are carriers of Powassan virus, and around 90% of mammals in New England “have serologic evidence of Powassan virus.”
To read the full interview transcript, click here