A female white-tailed deer (Odocoileus virginianus) whose ears are infested with ticks at Assateague Island National Seashore in Maryland.
Mary Swift/iStockphoto/Getty Images
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Mary Swift/iStockphoto/Getty Images
In 2020, during the COVID-19 pandemic, Virginia Barbatti moved with her family to Martha’s Vineyard full time.
It’s an idyllic beach island off the coast of Massachusetts, a summer retreat for presidents from Ulysses S. Grant to Barack Obama.
In the evenings, around dinnertime, deer roamed Barbatti’s yard. “That was really exciting for us when we first moved here,” Barbatti says. “It felt like we were connecting with nature and the outdoors.”
Fast-forward a few years, and Barbatti’s feelings have changed. “Knowing that there are thousands of ticks potentially on a deer as they’re walking through your yard, and they’re dropping and moving them across the landscape — it really starts to shift perspective.” She’s now director of a nonprofit, started in December 2025, called Tick Free Martha’s Vineyard.
Barbatti’s island haven is plagued with ticks — small arachnid parasites that live in the grass and woods, hitch rides on roaming animals and drink their blood.
When some types of ticks bite humans, they can provoke life-threatening allergies to red meat. Others can transmit bacteria that cause Lyme or other diseases.
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The months of May and June are, unfortunately, primetime for them. “According to our Tick Bite Tracker, ticks are out everywhere,” says Alison Hinckley, epidemiologist and Lyme disease expert with the Centers for Disease Control and Prevention. “We’ve seen a real uptick in areas where Lyme disease occurs.”
Almost all Lyme disease cases come from the Northeast, Mid-Atlantic and Upper Midwest, Hinckley says.
While it won’t be clear how this tick season compares with others until it’s over, it’s shaping up to be among the top three in the past decade, Hinckley says: “So it’s an important time to watch out for tick bites.”
Deer diary
The rise of tick bites and their diseases came with the resurgence of white-tailed deer, especially in the Northeast.
A hundred years ago, the white-tailed deer population was nearly wiped out in the region, says Lea Hamner, an epidemiologist focused on tickborne diseases. Many celebrated their return to the forests as a success for conservation efforts. Now, “we’ve overshot that comeback story significantly,” she says.
Hamner works with the Martha’s Vineyard Tick Program, an initiative of the local government. The island has an average of more than 50 deer per square mile — three to four times what state wildlife officials recommend.
Excess deer can damage forests by overforaging and increase the risk of collisions with cars. They also help grow tick populations. While ticks feed on various mammals and birds, they often find their mates crawling around on the broadside of a deer. “We like to call them the party bus or the singles bar for ticks,” Hamner says.
The ticks drop off the deer and lay eggs, wherever the deer roam. So more deer means more ticks.
For decades, it was deer ticks. Parasites that can transmit bacteria that cause Lyme disease.
Then, in 2011, the lone star tick moved up from the Southeast — probably on the backs of migrating birds. Their appearance sparked a new wave of panic, Hamner says.
Lone star tick bites are itchier and more unpleasant than deer tick bites, and they can gather in what Hamner calls a “tick bomb”: “When they’re babies, they stick together and they get on you all at once. They’re very, very small. But to have hundreds of tiny ticks on you is terrifying,” she says.
Then, there’s the alpha-gal syndrome. Lone star ticks have a sugar in their saliva that can cause life-threatening allergies to certain foods. “Red meat, mammalian meat, is the common denominator,” Hamner says. “Less people are also reactive to dairy products, which come from mammals as well.” Some also develop sensitivities to gelatin capsules used in medicines, and certain soaps and shampoos.
On Martha’s Vineyard, local chefs are trying to offer alpha-gal friendly food options, piecing their new menus together from the internet. “They don’t want to be armed with Google,” Hamner says. “I literally had a restaurant ask me, ‘Is there something better? Because I feel like this is not good enough for me just to be Googling to protect my patrons from having an allergic reaction.'”
Right now, there isn’t. The science and regulatory requirements are still catching up.
The ticks’ slow march
A few years after lone star ticks arrived on Martha’s Vineyard island, they came ashore to mainland Cape Cod — probably also on birds.
“The risk of developing an alpha-gal allergy is not consistent across all of the state,” says Catherine Brown, state epidemiologist at the Massachusetts Department of Public Health.
In April, the state became the 14th jurisdiction to require cases of alpha-gal syndrome to be reported, Brown says, in an attempt to track where the risks are high and where the condition is emerging.
In a cozy office space in South Yarmouth, Mass., where the walls are covered in posters of beetles and butterflies, Escher Cattle keeps his tick collection. He’s an entomologist and tick educator for the Cape Cod Cooperative Extension program in Barnstable County, which covers Cape Cod.
He pulls out glass vials with ticks preserved in alcohol. Some are from a nearby farm. The ticks are small — ranging from the size of a poppy seed to a sesame seed, depending on their life stage.
For someone who goes looking for ticks, Cattle has a good track record: “I’ve only gotten bit by ticks once in my time here so far,” he says.
His main tips are to pretreat outdoor clothing, starting with shoes, socks and pants, with an insecticide called permethrin, to wear EPA-approved insect repellent on exposed skin and to do a full-body tick check after you’ve walked through potential tick habitat. “Get really familiar with your different raised moles and everything so that you can really tell if a tick has attached to you,” he says.
Getting ticks off quickly lowers your chances of getting disease.
Beyond personal measures
Public health leaders say the onus can’t just be on individuals.
“Some people are very good about paying attention and doing the tick checks and using repellent,” says Brown with the state of Massachusetts. “But at the same time, we’ve continued to see the number of tickborne diseases, the types of diseases, and the numbers [of tick bites] generally increasing.”
In the near future, she hopes that a Lyme disease vaccine, developed by Pfizer, will be effective at preventing Lyme disease and approved by federal regulators. “It’s not a solution to the tick problem, but it could be an important tool to help reduce the most common tickborne diseases,” she says.
In the long term, she hopes researchers can figure out how to reduce tick populations.
But research on tick control lags behind mosquito control by decades. “We’ve been studying mosquitoes as a disease vector since the 1900s, so we know a lot of different things about what works on them,” Cattle, with Barnstable County, points out. “But for ticks, we’ve only really been studying them in this kind of capacity since the 1980s,” when the bacterium that causes Lyme disease was identified.
In the past few decades, researchers have tried multiple strategies, says Stephen Rich, executive director for the New England Center of Excellence in Vector-borne Diseases (NEWVEC) at UMass Amherst.
“We’ve tried spraying ticks on the yard, we’ve tried treating ourselves and even tried making nest boxes for mice where the mice can go and get treated. Nothing has worked the way we want it,” he says. They haven’t made big dents in the tick population or the number of tick bites people get.
Rich is adapting an idea from an oral medicine that protects pets, by making their blood toxic to fleas and ticks, for deer. “There’s some tricks to that,” he says. “There’s differences in the digestive system of white-tailed deer versus dogs and cats. And there’s also the fact that these are game animals, so they have to be treated as a food source.”
In New York City, Staten Island is trying a different solution for deer: controlling the population by sterilizing them. “Every male — or at least most of them — have had vasectomies,” says Maria Diuk-Wasser, a professor in the department of ecology, evolution and environmental biology at Columbia University who tracks tickborne diseases.
The bucks are tranquilized and sterilized in the procedure. She says they’re even watching for new deer coming in from New Jersey, to give them vasectomies too.
The project, which started in 2016, appears to be stabilizing the population. Very few new babies are born, “but the deer can live many years, so it’s not yet a drastic decline overall,” Diuk-Wasser says.
In late May, U.S. Health Secretary Robert F. Kennedy Jr. announced new federal investments in preventing, diagnosing and treating tickborne diseases.
Tick researchers say they’ll take what help they can get. It’s going to take more experimentation and time to figure out how to reduce the growing threat of ticks.
