Betsy Shay rarely eats red meat. But one day this summer, she decided to have a hamburger for lunch.

Six hours later, her life changed.

“I was dizzy, I was nauseous, I couldn’t figure out what it was,” the Aquinnah resident recalled this week. “It was nothing like I’ve ever had before.”

What she ended up having was alpha-gal syndrome, an allergy to red meat and potentially other mammalian products that has spread like wildfire across the Island in the last few years – raising concerns among health care officials who have no real treatment options.

The number of positive cases at Martha’s Vineyard Hospital has nearly quintupled in just the first nine months of 2024 when compared to all of last year. Cases first started to pop up about four years ago, though doctors on the Island and further afoot weren’t quite sure what they were seeing.

In 2020, the hospital recorded just two confirmed cases of alpha-gal sensitivity. By 2022, the number had jumped to 77. This year, as of Sept. 30, the hospital had 365 positive cases.

“Alpha-gal really wasn’t a concern on any of our radars four or five years ago, and now it is,” said Lea Hamner, an epidemiologist with the Inter-Island Public Health Excellence Collaborative, at a talk about the allergy hosted by the Vineyard Haven Public Library this week. “Everyone is one degree of separation now, at this point, away from someone with alpha-gal syndrome on Martha’s Vineyard.”

The syndrome’s rapid rise is due in part to lone star ticks’ spread around the Island. The ticks first appeared on the Vineyard around 2011, largely sequestered to Chappaquiddick and Aquinnah.

At the time, there was no rise in diseases or alpha-gal, but surveys done in recent years show the ticks are now found in every town, across all kinds of terrain, correlating with the explosion in cases of alpha-gal.

“No one is excused from the lone star anymore,” said Patrick Roden-Reynolds, the biologist who runs the Martha’s Vineyard Tick Program.

Before arriving on the Vineyard, the tick was largely confined to the southern and midwest regions of the U.S. Identified by the eponymous white dot on the back of adult female ticks, the arachnid is believed to thrive in new areas further north due to climate change.

Dr. Scott Commins, one of the foremost experts in alpha-gal syndrome, spoke before nearly 100 Islanders in a virtual presentation on Monday. He treats patients at the University of North Carolina School of Medicine allergy clinic, and has been researching the allergy that has baffled scientists.

Recent studies estimate the number of alpha-gal cases in the country have risen to 450,000 people, putting the syndrome at the 10th most common food allergen in the country, he said.

Researchers believe that lone star ticks carry the alpha-gal carbohydrate, something that is naturally occurring in mammalian meat, with the exception of primates. When a lone star tick bites a human, the human body will begin to make an allergic antibody that recognizes alpha-gal, giving people various allergic reactions when they come into contact with the carbohydrate again.

The issue with alpha-gal syndrome is the allergic reaction seems to be triggered far beyond a hamburger or steak dinner. Medications that have gelatin in them or even just the smell from a barbecue can cause discomfort, and a large number of patients report reactions to dairy.

“When we looked at this, about 30 to 40 per cent of our patients were bothered by dairy,” said Dr. Commins.

One of the confounding things for patients is that allergic reactions can vary so widely. The syndrome can trigger hives or even anaphylactic shock in some people. Others experience digestive issues, including Ms. Shay in Aquinnah. The allergy can often take hours to manifest, earning the syndrome nickname “the midnight allergy.”

“You can literally have a hamburger for dinner at 7 p.m. and nothing may happen until midnight or 1 a.m.,” said Dr. Commins. “So, you can imagine it makes diagnosis quite a challenge.”

He encouraged people with alpha-gal to carry epi-pens, as there is currently no treatment for the syndrome. The allergy does appear to wane though over time, and patients have successfully reintroduced dairy, red meat and other animal products back into their diets.

Dr. Gerry Yukevich, a physician at Vineyard Medical Care, said the rapid spread of the allergy has people worried, especially because the baby ticks, which appear no larger than a speck of dirt, seem to spread the alpha-gal as easily as the adults.

“At first people were wondering, what the heck is this,” he said. “Is it scabies or a parasite?”

This summer, dozens of people reported rashes and bites that appeared to have been from the larval ticks. Aubrey Stimola Ryan, a physician’s assistant at the hospital, said similar clusters of bites appeared last year as well.

Patients who have symptoms can get blood tests at the hospital, and Ms. Stimola Ryan said she will often send patients home with information resources and a prescription for an epi-pen.

“I don’t think a day goes by on one of my shifts where I don’t order a tick panel,” she said.

The new allergy has caused some anxiety in Islanders, who either are struggling with adjusting to a new diet or fear they will end up getting it. Dr. Yukevich had one patient say they were thinking of selling their property on the Island because they didn’t want their grandchildren to be allergic to meat.

“Unfortunately at this point, there’s not a whole lot you can do but be aware,” Dr. Yukevich said.

A support group was started this summer to help Islanders cope with the drastic change to their lives, and more than three dozen people attended the first meeting in July. Dr. Yukevich and others said as the allergy becomes more prevalent, restaurants may have to be more sensitive about displaying what animal products are used in the cooking process for a variety of dishes.

Ms. Shay has been learning to live with the allergy; she uses coconut milk instead of cow’s milk in her coffee and has been trying out vegan cheeses. She’s found a vegan butter that hits some of the notes of the real thing and will have to do for now.

“I step away from the grill now,” she said. “There’s never bacon in the house. I’m learning all the time.”