Female lone star tick
Each year, an estimated 31 million people in the U.S. are bitten by ticks. Tick bites, particularly from lone star ticks, can lead to alpha-gal syndrome (AGS), a serious and potentially life-threatening allergy to red meat and other animal products.
AGS can develop when a tick transfers alpha-gal (galactose-α-1,3-galactose), a sugar molecule found naturally in most mammals and in the saliva of some ticks, into a person’s bloodstream. Humans do not naturally produce alpha-gal, so the immune system sometimes mistakenly identifies it as a threat. Later, when a person with AGS eats red meat or is exposed to other products containing alpha-gal, their immune system can react, causing an allergic response which can range from mild to very severe.
When a person with AGS has an allergic reaction, symptoms can include itchy hives, stomach pain or upset, coughing, trouble breathing, or even a sudden, life-threatening reaction called anaphylaxis.
The Need for More Research
There is currently no cure or treatment for AGS, and no prevention strategies beyond avoiding tick bites. To address these knowledge gaps, NIAID is supporting vital research both in its own laboratories and by supporting researchers at universities across the country. Researchers are focusing on some key questions, such as:
- What are the body’s immunologic responses to lone star tick bites?
- Identifying biomarkers that could predict or characterize an allergic reaction.
- Investigating how molecules in tick saliva trigger the body's immune system to help understand how tick bites lead to the development of AGS.
- Determining human genetic factors verses tick-related triggers in the development of AGS.
- How can we prevent development of AGS and other tick-borne illnesses?
- Developing vaccine strategies that block ticks from feeding on humans and reduce alpha-gal sensitization.
- Creating genetically altered ticks to inhibit reproduction, control population levels, and slow the spread of alpha-gal from tick saliva to the bloodstream.
- Developing materials that slowly release tick repellents, including granules that could be used in landscaping and treated fibers that could be used in protective clothing.
- How are we creating diagnostic, treatment, and cures strategies?
- Developing a comprehensive panel of human alpha gal–specific antibodies to inform improved diagnostics and therapies.
- Studying whether carefully supervised food challenges can safely diagnose AGS.
- Tracking AGS cases across the country to better understand where and how often it occurs and who is affected.
Tick-related Factors – One possible way to prevent AGS and other tickborne diseases is by developing more effective methods of preventing tick bites. NIAID research is currently exploring how to prevent tick bites in multiple ways, including by blocking ticks from feeding, controlling tick populations, and creating novel tick repellents.
Host Factors – Improving our understanding of the human immune system may help prevent or treat AGS. Current NIAID research is examining how the immune system responds to tick bites, tick saliva, alpha-gal, and other factors. Findings from this research could help guide the development of new tools to diagnose, prevent, and treat AGS and other tickborne diseases.
Alpha-gal – Research focused on alpha-gal helps scientists better understand how AGS develops, how often it occurs, and how it can be diagnosed more accurately. Current studies include evaluating supervised oral food challenges as a safe diagnostic tool, as well as examining AGS epidemiology.
Funding Opportunities
Researchers are always welcome to submit investigator-initiated grant applications on topics relevant to alpha-gal syndrome that fall within the NIAID mission. Additionally, researchers can respond to specific requests for applications issued or supported by NIAID, which are available on NIH’s Highlighted Topics page and at Grants.gov.