Alpha-gal syndrome, which can trigger a potentially fatal meat allergy, is surging across the U.S. Why?
What causes alpha-gal syndrome?
It often begins with a bite from a lone star tick, which has a sugar molecule known as alpha-gal in its saliva. That molecule is found in the tissues of most mammals, but not humans, and normally causes no problems when people consume it in red meat. But when alpha-gal enters the bloodstream via a tick bite, the body produces antibodies to fight the intruder. In about 50% of people with those antibodies, a subsequent exposure to alpha-gal—such as by eating beef, lamb, pork, or venison—can spark an overactive immune response that causes hives, joint pain, vomiting, and severe abdominal cramps. “It was a terrifying experience,” said Roanoke, Va., resident Heather O’Bryan, who in 2019 found herself struggling to breathe after eating a pork sausage. “I didn’t know I had an allergy, but it almost killed me.” In extreme cases, alpha-gal syndrome (AGS) can cause anaphylactic shock and death. The U.S. confirmed its first alpha-gal death in November: a 47-year-old New Jersey airline pilot who collapsed in 2024, four hours after eating a burger at a barbecue. Thousands of people are now diagnosed with AGS each year, a remarkable number considering the syndrome was formally identified only in 2007. “Alpha-gal has gone from a medical curiosity to a major public health issue in just a decade,” said Vinay Jahagirdar, a gastroenterologist at Virginia Commonwealth University.
How many people have AGS?
More than 110,000 suspected cases were identified from 2010 to 2022, according to the Centers for Disease Control, which estimates that up to 450,000 people may be affected. Some doctors believe that’s an undercount. A study co-authored by Jahagirdar found a hundredfold increase in positive tests for alpha-gal antibodies between 2013 and 2024. Once clustered in the Southeast, the traditional habitat of the lone star tick, the disease is now common across the Northeast and Midwest and is surging along with other tick-borne conditions such as Lyme disease. Scientists say the warming climate has allowed lone star ticks to move north to areas where it was previously too cold for the species to thrive; the parasites have also been aided by the booming population of white-tailed deer, their primary host. Lone star ticks are especially aggressive and move three times as fast as the black-legged tick. “They will hunt you,” said Sharon Pitcairn Forsyth, a conservationist and founder of the Alpha-Gal Alliance. “They are like a cross between a lentil and a velociraptor.”
What are the signs of infection?
There aren’t any, so most people don’t know they have AGS until they suffer an allergic reaction. But getting a diagnosis can be a long journey, both because many doctors aren’t familiar with alpha-gal and because symptoms can take up to six hours to appear after an exposure. Andrew Keenan, 58, a telecoms repairman in Martha’s Vineyard, Mass., woke up with severe stomach cramps at 2 a.m. after a skirt-steak dinner. He then broke out in hives, and his blood pressure fell so low that “I sat up in bed and almost fainted.” Keenan, who was treated at the hospital for anaphylactic shock, now gets cramps and itching that can last days when he accidentally consumes alpha-gal, but reactions vary widely. Some are allergic to pork but not beef or vice versa; some react to dairy, some don’t. “Reactions are consistently inconsistent,” said Patrick Roden-Reynolds, a biologist who studies tick-borne diseases.
Why didn’t the thaw last?
On the campaign trail in 2016, Trump pledged to undo Obama’s policies—promises that helped him win the votes of a majority of Cuban Americans in Florida. In office, he imposed a “maximum pressure” campaign against Cuba and put the country back on the list of state sponsors of terrorism. Though President Joe Biden reversed that move in his last week in office in January 2025, Trump quickly reimposed it after returning to the White House last year with a newfound interest in Latin America, heavily influenced by Secretary of State Marco Rubio, a foreign policy hawk and the son of Cuban immigrants. Trump’s first target was Venezuelan autocrat Maduro, a close ally of Cuba, and many Cuban Americans saw that intervention as a step toward realizing Rubio’s desire to topple the island’s communist government. “If I lived in Havana, and I was in the government, I’d be concerned—at least a little bit,” Rubio warned hours after the January raid that captured Maduro.
Is there a treatment?
No. The only way to manage the disease is to avoid alpha-gal—which is trickier than just ordering halibut instead of lamb chops at a restaurant. Food can easily be cross-contaminated, and aerosolized fat molecules from sizzling meat can cause a reaction, as can many items with mammal-derived ingredients: dairy products; foods with gelatin; medications made with glycerin; personal-care products that contain collagen or lanolin; even sugar, which is processed with animal-bone char. “I’m nervous about everything I eat,” said Jamie Ridgway, a Virginia Beach resident who landed in the ER after eating a marshmallow. Some sufferers now avoid restaurants and dinner invites. “You don’t want to be the social pariah asking people, ‘Is this vegan? What about that?’” said Massachusetts teacher Kate Sudarsky, 26.
How do people cope with AGS?
Support groups are growing in hard-hit areas. O’Bryan of Roanoke reports an “almost constant” stream of new members to the online groups she’s joined. In high-incidence states like Virginia—where up to 1 in 50 residents of some counties has AGS—a growing number of restaurants offer alpha-gal-free dishes. Some eateries “have gone completely alpha-gal free,” said Pitcairn Forsyth, who notes “a lot of chefs have”AGS. Many sufferers carry EpiPens to treat severe reactions; they include Missourian Annie Kittrell Poehlein, who at home now has “separate pots and pans and cutting boards. I have my own barbecue grill; we have two ovens.”
What are health authorities doing?
A growing number of states track cases; 12 now mandate reporting of positive tests, including Kentucky, Virginia, and Massachusetts. Health officials are trying to raise awareness of the condition and to educate people on how to avoid tick bites. Meanwhile, researchers are attempting to solve a number of mysteries, including the reason reactions vary so widely, why the allergy sometimes fades over time, and whether people who carry alpha-gal antibodies but show no visible allergic response might suffer unseen health effects, including digestive problems or coronary disease. Treatment breakthroughs may be on the way, but in the meantime, experts expect AGS to keep spreading. “It seems like an oddity now,” said Brandon Hollingsworth, a University of South Carolina epidemiologist, “but we could end up with millions of people with an allergy to meat.”