A once-rare disease that causes a severe allergy to red meat is seeing an “explosive rise” across America, health experts warn. And the ailment comes from ticks.
Alpha-gal syndrome is a tick-borne disease that has seen a 100-fold increase between 2013 and 2024, which experts warn now makes it a major public health issue. Lyme disease appeared alongside 17% of diagnosed AGS cases, "suggesting an overlapping risk from tick exposure," experts said.
Why is this happening? Climate change is the main culprit because the lone star tick that's associated with AGS has spread beyond southeastern states due to warmer weather across wider stretches of the U.S. AGS as it's known causes hives, swelling, nausea, vomiting, abdominal pain, and diarrhea, with the potential for life-threatening anaphylaxis shock.
“Alpha-gal syndrome is unlike any other food allergy we treat,” said Vinay Jahagirdar, M.D., the study’s co-author with VCU Gastroenterology Fellowship Training Program and Stravitz-Sanyal Institute for Liver Disease and Metabolic Health. “Symptoms often appear several hours after a person eats red meat, making it difficult to connect a meal with an allergic reaction. Many patients are misdiagnosed or go years without answers.”
AGS happens when the tick bite causes the infected person’s immune system to develop antibodies to a sugar molecule found in the meat of mammals such as beef, pork or lamb. But it can take six hours after consumption for symptoms to start, so experts say AGS is often misdiagnosed.
“The spread of ticks is bringing new allergic diseases to areas where doctors and patients may not expect them. Recognizing this connection is key to protecting public health,” said Ravi Vachhani, M.D., study co-author.
While AGS is incurable, antibody levels decline over time and can let those affected eventually reintroduce alpha-gal-containing products into their diet.