MARTHA'S VINEYARD — Patrick Roden-Reynolds, the public-health biologist for Martha's Vineyard, is cautioning residents and visitors about an increasing presence of tick-borne diseases on the island. He has collected eighty-one ticks, arranged in neat rows by sex and species, including dog tick, deer tick, and lone-star tick.

Between 2020 and 2024, Martha's Vineyard experienced nearly nine hundred cases of Lyme disease and babesiosis. These diseases are eleven times more common on the island than in mainland Massachusetts. Anaplasmosis is five times more common on Martha's Vineyard compared to the mainland.

Ticks on Martha's Vineyard can transmit almost a dozen different diseases. Lyme disease, caused by bacteria in deer ticks, can lead to flu-like symptoms, chronic fatigue, and arthritis if untreated. It is typically curable with antibiotics such as doxycycline or amoxicillin. Babesiosis began to spread on Martha's Vineyard in the early 2000s, causing chills, high fever, nausea, and, in rare instances, hemolytic anemia. Unlike Lyme disease, babesiosis does not respond to antibiotics alone. Anaplasmosis also spreads fevers and chills.

Roden-Reynolds has noted the expanding range of lone-star ticks on Martha's Vineyard, which were first confirmed on the island in 2011. He has discovered these ticks on walking trails, benches, in toolsheds, parking lots, and in the yards of hundreds of local homes he has surveyed. Fifty years ago, lone-star ticks rarely appeared north of the Mason-Dixon Line, but they have since expanded their range north to Maine and west to the Oklahoma panhandle. Alpha-gal syndrome is currently the most rapidly spreading tick-borne illness in the United States.

Dick Johnson, Roden-Reynolds' predecessor as public-health biologist, contracted Lyme disease four or five times between 1990 and 2001. He recalled a time when receiving a blood test for the disease was uncommon. "It was no big deal," Johnson said. "Usually, they didn't even give you a blood test." Johnson noted that some individuals, after contracting a combination of Lyme, babesiosis, and anaplasmosis, ended up in intensive care units. "Sometimes they'd get the trifecta of Lyme, babesiosis, and anaplasmosis, and end up in the I.C.U. fighting for their lives," he said.