 Maine has one of the oldest populations in the nation, and the Maine Center for Disease Control reports that cases of Lyme disease in adults 65 and older have grown at an alarming rate. In 2022, about 1,000 Lyme cases of the more than 2,600 reported were in that age group. Dr. Mark Abel, infectious disease physician at Northern Light Eastern Maine Medical Center, says he isn't sure exactly why that demographic is experiencing more tick-borne illness, but says older adults have weaker immune systems.