The time frame in which deer ticks are active in Maine appears to be growing. Chuck Lubelczyk of the Maine Medical Center Research Institute Vector-Borne Disease Lab said from southern Maine to Acadia last year, deer ticks were active all the way into December.
"That actually meant that we had reports of tick-borne disease coming in in late November, December, which is not something we normally think about as the norm," he said.
Deer ticks became active again in late February of this year, said Lubelczyk, which is earlier than usual. He said the longer tick season is influenced by milder winters and less snow pack.
The lab is conducting studies to better understand how deer ticks are able to survive winters. Scientists are also doing research into how the Powassan virus spreads among ticks. It's one of several diseases they can transmit to humans. Staff scientist Rebecca Robich said habitat may play a role.
"What we noticed when we were doing the study, is that there were certain sites where we were collecting from that came up positive with Powassan time and time again," Robich said.
The habitats in which Powassan is most prevalent in ticks, she said, are in forests with thick understories of invasive shrubs such as barberry and honeysuckle. Scientists at the lab are now trying to understand why Powassan is found at higher rates in those habitats.
The Maine CDC announced last week that a resident from Waldo County died from Powassan virus after being bitten by a tick and developing neurologic symptoms. Maine has recorded 14 cases of Powassan and three deaths since 2013.
Deer ticks can also transmit Lyme disease, anaplasmosis, and babesiosis. Scientists at the lab say it's important for people to take precautions and do tick checks on themselves and their pets, which often bring ticks into homes. People can also make their yards less hospitable to ticks by removing brush, leaves, and invasive species such as barberry, bittersweet, and honeysuckle.
People seeking additional information about ticks and tick control methods can find resources on MMCRI’s website including:
- Tips on controlling ticks and mosquitoes, as well as how to remove attached ticks
- Descriptions of ticks in Maine
- Information on tick-borne diseases
- The CDC also has several resources with more information on vector-borne diseases on its website.