The Maine Center for Disease Control and Prevention is warning people who live and visit the state to avoid tick bites as data indicates the state has either broken records for certain tick-borne illnesses or is on track to break them.
In a news release sent to media on Thursday, the agency said officials said four cases of Powassan virus this year broke a previous record and warned that there is an uptick in adult deer tick activity in Maine from “late September through November.”
The diseases on track to break records included Lyme disease, anaplasmosis, babesiosis and hard tick relapsing fever, with 1,977 cases, 677 cases, 161 cases and 10 cases, respectively.
To prevent tick bites, officials at Maine CDC are urging people to “know when you are in tick habitat and use caution, wear light-colored clothing that covers the arms and legs and tuck pants into socks and perform tick checks daily after any outdoor activity.”
"My initial reaction was that I’m glad that there’s so much more attention being paid to this," said Dr. Meghan May, a professor of microbiology and infectious disease at the University of New England.
"It’s terrifying in that these are diseases that in many cases leave people with lifelong disabilities," said May, explaining that she hopes the cases raise awareness of tick safety.
As the state urges people to take precautions, May said she is also thinking about what is causing the diseases to increase in prevalence.
In addition to climate change bringing warmer weather to Maine that is favorable to ticks, May says there is evidence of a mouse population boom.
She sees that increase in mice combined with more development abutting wooded areas as a factor contributing to more cases of these illnesses.
The latter change means that there may be fewer predators proximate to mice to hunt them.
"We’re having a high mouse year but we’re also seeing a kind of sustained effect of that removal of natural predators," she said.
There could also be something else at play.
While, as May mentioned during her interview, there is a Lyme disease vaccine on the horizon and there is more antibiotic intervention for both that illness and anaplasmosis, when it comes to other diseases like Powassan virus, there is no similar vaccine in development.
At the same time, May says ticks “seem to be carrying [Powassan virus] at a higher rate than they did in the past.”
“My lab has done some work on this, as have a group at Princeton University and I’ve done this work with some colleagues in the Midwest,” she explained, adding that “it’s not clear why it’s happening.”
“What that means for human health I think remains to be seen,” she noted.
May is hopeful new research will be done to further the understanding of Powassan, especially given the severity of some of its symptoms.
According to the Maine CDC, one of the people who contracted the illness in Maine this year died after experiencing neurologic symptoms.
The illness can also cause encephalitis.
May hopes any new data that is gathered could answer questions like whether or not there are also cases of Powassan virus where people do not have symptoms at all.