UNMC’s Shaun Cross, PhD, has published the first peer-reviewed study of farmers and ranchers living with alpha-gal syndrome (AGS), a tickborne allergy to red meat, in the Journal of Agromedicine.
Dr. Cross, an assistant professor in the UNMC Department of Environmental, Agricultural, and Occupational Health of the UNMC College of Public Health, surveyed more than 200 farmers and ranchers across 26 states on their experiences with tick bites, AGS awareness, symptoms and obtaining a diagnosis.
What is Alpha-gal
Alpha-gal is a molecule (galactose-α-1,3-galactose) that is naturally produced in the bodies of most mammals but not in people. It is also found in the saliva of some ticks, most commonly the lone star tick. When a tick bites, it can transfer alpha-gal from its saliva into a person’s body. The body’s natural defenses, or immune system, can identify alpha-gal as a threat and trigger an allergic reaction. Symptoms can range from mild to severe, and some may be life-threatening. Symptoms occur after people eat mammalian meat such as beef, pork, or venison or are exposed to other products made from mammals, including dairy and medications. Because of this, AGS is also sometimes known as red meat allergy or tick bite meat allergy.
More than 110,000 suspected cases of AGS were identified in the United States between 2010 and 2022. However, cases of AGS are not nationally notifiable to CDC. The actual number of AGS cases in the United States is not known, but as many as 450,000 people may be affected.
Key findings included:
- On average, individuals had three healthcare provider visits prior to diagnosis though some reported more than 10 visits.
- The most common medical providers that diagnosed individuals with AGS were general practitioners and allergists.
- Individuals were uniquely grouped into one of four AGS symptom classes and symptoms can differ by sex.
“The purpose of this survey was to understand how this emerging allergy was impacting the farming and ranching community members with AGS by asking them questions about their work, their physical health and their mental health,” Dr. Cross said. “We received great feedback and are excited to share this information across a series of publications and stories.”
In the United States, AGS is spread primarily through the bite of the lone star tick. In recent years, the lone star tick has expanded beyond its traditional range in the southeast United States and into areas previously too cold for them. Most of the survey respondents lived in Missouri and Oklahoma.
Alpha-gal syndrome affects nearly half a million Americans, according to estimates from the Centers for Disease Control and Prevention. For farmers and ranchers who are in close contact with livestock every day, the allergy can be especially challenging.
Dr. Cross said the research team heard from people who’ve had to hire more help, stop raising livestock or leave farming altogether.
“The idea of a person shutting down a farm that’s been in their family for generations because of this new diagnosis, I can only imagine what that feels like,” Dr. Cross said. “That has to be devastating.”
Dr. Cross was invited to present results of the study at the first National Convening on a National Strategy for Alpha-gal Syndrome, hosted by Food Allergy Research and Education (FARE), on Oct. 27-28, in Washington, D.C. He emphasized the importance of recognizing the broader impacts of AGS in occupational health, particularly within rural and agricultural communities.
“Farmers and ranchers are at an increased risk of exposure to ticks from working outdoors,” Dr. Cross said. “It’s crucial that healthcare providers, especially those in rural areas, are better equipped to recognize AGS symptoms and understand the unique occupational implications for these individuals.”