Recent case reports suggest an expanding threat of tick-borne alpha-gal syndrome over much of the continental United States. Until recently, the lone star tick (Amblyomma americanum) was the only species implicated in transmission of this unusual adverse reaction. Our new research, however, has unveiled something unexpected yet critical. The black-legged tick (Ixodes scapularis) and western black-legged tick (Ixodes pacificus) transmit alpha-gal syndrome. This concerning find boosts the prevalence of meat allergicity due to galactose-alpha-1,3-galactose (alpha-gal). It is hitting areas once thought immune to its impact.
Alpha-gal syndrome is a dangerous mammal meat allergy. It forces your body to produce an immune response to alpha-gal, a carbohydrate present in all mammalian meats including beef, pork and lamb. The black-legged tick, prevalent in the eastern half and Midwest of the U.S., and the western black-legged tick, found along the West Coast, are now implicated in spreading this condition. People living or traveling to these areas need to protect themselves from being bitten by ticks. This goes a long way toward protecting them from developing alpha-gal syndrome and other tick-borne diseases.
Today, the NIH has the original alpha-gal syndrome in the United States. This new finding was published in the April 4 edition of the CDC journal Emerging Infectious Diseases. This case was about a 74-year-old woman from Maine who experienced neurological symptoms after a known bite from an infected black-legged tick. The second case, published in the same journal, was a 61-year-old Washington State wildlife biologist. Both of these cases highlight the increased geographical risk that these newly established tick species bring.
Symptoms of alpha-gal syndrome range from mild to life-threatening. Symptoms can range from inflammation and itchiness at the bite site to abdominal pain to a general malaise. Case in point, a 45-year-old woman experienced life-threatening diarrhea and vomiting within hours of consuming undercooked beef. This frightening response prompted her to receive medical care 20 days after being bitten by an infected tick.
Now, experts are calling for more awareness and more research into the process by which tick bites induce alpha-gal syndrome. Dr. Johanna Salzer stated, “More studies are needed to discover details about how a tick bite triggers alpha-gal syndrome in some people, and why bites from lone star ticks appear to cause the majority of the human cases in the United States versus blacklegged, western blacklegged, and other ticks.”
Retiring professor Jennifer Platt explained that other tick species have been suspected of carrying this condition for years. She remarked, “With thousands of Lyme [a tick-borne disease] patients telling us they can’t tolerate red meat, we’ve long suspected black-legged ticks and other tick species in the US.”
Avoiding tick bites is still the best way to protect yourself from alpha-gal syndrome. Health officials continue to urge the public to apply EPA-registered insect repellents. They additionally recommend using permethrin-treated clothing when you go into areas where you know ticks will be present. Dr. Salzer advised, “When you anticipate being in areas where ticks may live, use an EPA-registered insect repellent and wear permethrin-treated clothing.”
