Key Takeaways:
The lone star tick has triggered more than 5,500 confirmed alpha-gal syndrome cases in Missouri since 2017, pushing state lawmakers and researchers to expand tracking and treatment.
More than 5,500 Missourians tested positive for alpha-gal syndrome between 2017 and 2022, according to CDC data, as the lone star tick's expanding range drives a surge in the red meat allergy across the state.
"You don't learn about it in med school — it was completely new to me," said Dr. Benjamin Casterline, a dermatologist and alpha-gal researcher at MU Health Care.
The CDC study tested 357,119 people over the five-year period, with nearly all of Missouri shaded dark blue on the agency's map indicating the highest case counts. The disease, triggered when the lone star tick's saliva introduces the alpha-gal sugar molecule into the bloodstream, can cause reactions ranging from hives and nausea to life-threatening anaphylaxis after consuming red meat or dairy.
Without mandatory reporting, Missouri has struggled to qualify for federal funding — a CDC grant for AGS education and awareness requires demonstrated burden of disease, putting the state at a disadvantage against those that have tracked cases for years.
State Rep. Matthew Overcast, a Republican from Ava, sponsored HB1855 after the disease affected his own family — three of his five children, his wife, his brother and his aunt all have alpha-gal. The legislation, which passed and now awaits the governor's signature, requires laboratories to report positive AGS results to the Department of Health and Senior Services within seven days of confirmation. DHSS will have six months to begin publishing case data once the bill becomes law.
"Each year, cases were growing and becoming more complex," Casterline said. The new reporting system will allow researchers to map hot spots across Missouri and track changes annually, data that could unlock federal resources.
The CDC's most recent notice of funding for AGS education and awareness requires states to demonstrate disease burden. States that have been counting alpha-gal cases for years have a clear advantage in qualifying. Missouri's data, drawn from a 2022 study, is now several years old.
Researchers are still working to understand why the lone star tick carries the alpha-gal molecule. Early theories suggested the tick acquired it from biting deer, but Casterline said the molecule appears even in ticks fed on human blood, indicating the tick produces alpha-gal through its own saliva.
There is no cure for alpha-gal syndrome. Patients must avoid mammalian meat — beef, pork, lamb — and dairy products. Symptoms vary widely: some experience only hives or indigestion, while others suffer anaphylaxis requiring epinephrine injections. Repeated tick bites can amplify the body's reaction.
In southwest Missouri, Katrina and Alec Hagan opened The Safe Spoon in Springfield, a cafe catering to customers with AGS and other food allergies. Alec, a former agriculture teacher diagnosed with alpha-gal several years ago, found that even being near pigs and sheep could trigger flare-ups.
With lone star ticks expanding across the U.S., prevention remains the primary tool. The CDC recommends EPA-approved repellents containing DEET at 20 percent to 30 percent concentration, picaridin at 20 percent or oil of lemon eucalyptus at 30 percent on exposed skin every two to four hours. Clothing should be treated with permethrin at 0.5 percent concentration, which lasts through multiple washes.
Farmers and ranchers face elevated risk. Regular tick checks after outdoor work are critical, as even treated clothing does not guarantee protection. The lone star tick's range now extends across the eastern U.S., with cases concentrated in the Southern, Midwestern and Mid-Atlantic regions.
Nationally, tick-borne illnesses are at their highest level in a decade. Lyme disease alone affects nearly 500,000 Americans annually, according to CDC estimates. Powassan virus, a rare but often fatal tick-borne disease, reached a record 76 diagnosed cases in 2025. Alpha-gal syndrome, while not a traditional infectious disease, has become one of the most disruptive tick-borne conditions due to its lifelong dietary restrictions.
The implications extend beyond individual health. Missouri's experience shows how gaps in disease surveillance can delay federal funding and research. With the new reporting law, the state hopes to close that gap — but the tick population continues to expand, driven by warmer winters and suburban sprawl that have pushed deer and tick habitats closer to human populations.
This article is for informational purposes only and does not constitute investment advice.
