Researchers say they believe they've documented the first known death from alpha-gal syndrome — a red meat allergy caused by tick bites.
The findings, by researchers at the University of Virginia School of Medicine, published in the Journal of Allergy and Clinical Immunology. The report says a 47-year-old airplane pilot in New Jersey fell ill four hours after eating a hamburger at a barbecue in 2024. The man's son found him unconscious on the floor of a bathroom surrounded by vomit. The man was declared dead at a hospital. The autopsy cited a "sudden unexplained death."
Two weeks before he died, the man had become ill several hours after eating a steak dinner, waking up with abdominal discomfort, writhing in pain, having diarrhea and vomiting. "I thought I was going to die," he told his son. But the man and his wife decided not to consult a doctor, saying they weren't sure how to explain what had happened.
A blood sample collected after the man's death showed he had an allergic reaction. His wife said that earlier that summer, he had 12 or 13 "chigger," or tiny mite larvae, bites around his ankles that left itchy, small bumps. But scientists believe those bites were actually from larvae of lone star ticks, which can cause alpha-gal syndrome.
What is alpha-gal syndrome?
Alpha-gal syndrome is a tick-borne illness that causes a red meat allergy.
Alpha-gal is a sugar molecule found in mammals like cows, pigs and lambs. It's also found in the saliva of some ticks. Humans don't produce the molecule so when a tick transmits it, alpha-gal can produce a hive-like rash or an anaphylactic reaction about 2-6 hours after a person consumes meat.
"It is like it is trying to fight off," said Saravanan Thangamani, who directs the SUNY Center for Vector-Borne Diseases at Upstate Medical University. "It is a foreign body. But basically, as a result of that, we have this anaphylactic shock or allergy."
The Centers for Disease Control and Prevention said there were more than 110,000 suspected cases identified between 2010 and 2022. But the CDC said the number of cases is likely higher, with as many as 450,000 people affected, as many people are unaware of the allergy and it requires a diagnostic test.
In a report released in July 2023, the CDC said 42% of surveyed health care providers had never heard of the disease.
The American Gastroenterological Association advises people with unexplained diarrhea, nausea and abdominal pain to be tested for alpha-gal syndrome.
In the U.S., alpha-gal syndrome is primarily associated with lone star ticks, according to the CDC. Most reported cases occur in the South, East and Central states, where lone star ticks are common.
Thangamani, who runs the Upstate Tick Testing Laboratory in New York, said the number of lone star tick encounters this year in that state sent to his lab doubled from 2024. And he notes a trend of lone star ticks migrating north.
"In 2023, we received ticks from seven counties in New York State that are lone star tick encounters," Thangamani said. "This year we got about 15 counties. In addition to increasing numbers, they're also expanding in geographic range, so this is a cause of concern."
How can I protect myself?
There is no vaccine to prevent alpha-gal syndrome. After infection, physicians recommend patients change their diet to avoid consuming meat such as beef, pork, lamb, venison, or rabbit.
Thangamani said preventing tick bites is key to avoiding tick-borne illnesses. This includes wearing repellent like DEET, protective clothing and avoiding tick habitats.
If you are bitten by a tick, remove it as quickly as possible and save it in a plastic bag. That way doctors could identify what kind of tick it is and even test it for disease.
"We can't reduce the tick exposure, but if we can remove the tick as soon as we come from an outdoor activity, we essentially eliminate a lot of issues that arise after a tick bite," Thangamani said.
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