Academic and health care investigators are learning more about the complex web of factors driving the expansion of tick habitat, including global warming.

The changing climate in Maine caused by global warming is potentially creating new tick habitats and accelerating the spread of Lyme disease, according to research being done in the state.

Maine Medical Center Research Institute in Scarborough is partnering with the University of Maine’s Climate Change Institute to study how climate change affects deer ticks and Lyme disease.

Susan Elias, a disease ecologist at the research institute, said persuasive research connects climate change with the increased range of the deer tick that carries Lyme disease, but there hasn’t been a comprehensive look at the many factors that are causing a surge in Lyme cases. Those factors include shorter winters, hotter summers and fewer days of extreme cold temperatures.

The number of confirmed Lyme cases in Maine reached an all-time high of 1,464 in 2016 and has exceeded more than 1,000 a year since 2011. In the early 2000s, fewer than 300 confirmed cases were recorded each year.

Anaplasmosis, another disease transmitted to humans by the deer tick, emerged as a threat in 2017, with a record 400 cases reported through October. Many Mainers are now being co-infected with Lyme and other tick-borne diseases like anaplasmosis, although there are no public health data tracking co-infections. Researchers, however, are finding more ticks that carry both Lyme and anaplasmosis.

Elias said weather conditions in 2016 led to erroneous expectations that showed scientists how much more they still have to learn about the ticks that carry Lyme.