Protect against tick-borne Alpha-gal syndrome (AGS)

Alabama’s warm, humid climate creates perfect conditions for ticks and mosquitoes to breed. Each year, residents are urged to take proactive steps to protect themselves and their families from the range of vector-borne diseases they carry. Ticks can spread bacteria, viruses, and pathogens that cause disease in humans, and we are in peak tick season.

A serious and potentially life-threatening allergy to ticks is emerging as a public health concern – Alpha-gal syndrome (AGS). According to the Centers for Disease Control and Prevention (CDC), the actual number of AGS cases is unknown, but as many as 450,000 people may be affected.

AGS is an allergy to alpha-gal, a sugar molecule naturally produced in most mammals but not in humans, that can develop after a tick bite. Alpha-gal is also found in the saliva of some ticks. When a tick bites, it can transfer alpha-gal from its saliva into a person’s blood. The body's immune system can identify alpha-gal as a threat and trigger an allergic reaction. Symptoms occur after people eat red meat or are exposed to other products made from mammals. Because of this, AGS is also known as red meat allergy or tick bite meat allergy. Food products that contain milk and milk products may also contain alpha-gal. The lone star tick is a dominant species in Alabama, and it is most often associated with AGS.

AGS is a mysterious condition that often goes undiagnosed. The reason why certain people develop AGS and others do not is unknown. Most cases of AGS have been reported in adults, but people of all ages can develop AGS. Unlike most food allergies, it can take months for a person to experience AGS symptoms after being bitten by a tick.

Symptoms range from mild to severe and usually appear 2–6 hours after consuming red meat or dairy products. Symptoms may also appear after exposure to various products containing alpha-gal, such as gelatin-coated medications. Reactions can include hives or itchy rash, nausea or vomiting, severe stomach pain, heartburn or indigestion, diarrhea, cough, shortness of breath or difficulty breathing, drop in blood pressure, swelling of the lips, throat, tongue or eyelids, dizziness or faintness and anaphylaxis. Anyone having a severe allergic reaction or anaphylaxis should seek immediate emergency care. This is important; anaphylaxis is potentially life-threatening and involves multiple organ systems.

AGS is not a nationally notifiable condition; however, the department believes tracking it is of public health importance. In May, the State Committee of Public Health approved a proposed revision to the Rules for Notifiable Diseases for public comment that would require laboratories to report AGS.

The following recommendations from the CDC are ways to prevent tick bites:

• Know where to expect ticks. Ticks live in grassy, brushy, or wooded areas, or even on animals. Spending time outside walking your dog, camping, gardening, or hunting could bring you into close contact with ticks. Many people get ticks in their own yard or neighborhood. Avoid contact with ticks in areas with high grass and leaf litter and walk in the center of trails.
• Treat clothing and gear with products containing 0.5 percent permethrin. Permethrin can be used to treat boots, clothing, and camping gear and remain protective through several washings. Alternatively, you can buy permethrin-treated clothing and gear.
• Wear long sleeves and pants when outdoors, especially in wooded or grassy areas. Wear shoes, socks tucked into your socks, a long-sleeved shirt, a hat, and gloves.
• Use Environmental Protection Agency (EPA)-registered insect repellents containing DEET, picaridin, IR3535, Oil of Lemon Eucalyptus (OLE), para-menthane-diol (PMD), or 2-undecanone. When used as directed, EPA-registered insect repellents are proven safe and effective, even for pregnant and breastfeeding women.
• If using sunscreen, apply sunscreen first and insect repellent second.
• Check your body for ticks daily, especially after outdoor activities.
• Shower as soon as you come indoors and remove ticks promptly with tweezers.

Much remains unknown about AGS treatment, but people with AGS can manage this allergy with the help of their healthcare provider.

For more information about AGS, visit ADPH's Tick-borne Diseases and the CDC's About Alpha-gal syndrome.

Remember, careful prevention of tick bites greatly reduces the risk of AGS and other tick-borne illnesses, so please take precautions when exposed to ticks.

Scott Harris, M.D., M.P.H.
State Health Officer