This Tick Bite Can Cause Alpha-Gal Syndrome—Making You Allergic to Meat

A single tick bite can reprogram the immune system and trigger an allergy to red meat, scientifically known as alpha-gal syndrome. While still relatively new to the UK, the condition has been studied and documented in the US and Australia.

Tick bites are widely known to cause Lyme disease, but they can also cause a rare allergy called Alpha-gal Syndrome.

According to the Centers for Disease Control and Prevention (CDC), Alpha-gal Syndrome or AGS is caused by a lone star tick bite, but other countries also associate AGS with other species of tick. The Alpha-gal syndrome is a serious, potentially life-threatening allergy and tick-borne disease.

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 (spit) of some ticks.

AGS is also referred to as red meat allergy or tick bite meat allergy, develops when a tick bite transfers alpha-gal from its saliva into a person's bloodstream.

This prompts the immune system to recognise alpha-gal as a threat, leading to an allergic response.

Patients usually present with urticaria 4–6 hours after consuming red meat or other products derived from mammals.

The condition is most commonly seen in individuals with a history of tick exposure or multiple bites, and diagnosis is confirmed through specific immunoglobulin E (IgE) serology.

While people of all ages can develop AGS, most cases have been reported in adults.

Most reported cases of AGS in the United States occur in the South, the East, and the Central states. These are the areas where most lone star ticks are found. Furthermore, the cases in the US are surging due to ticks from climate change.

In the UK, AGS is fairly new as it was first described in 2019, caused by foreign ticks in travellers returning to the UK.

These Scottish case reports confirm that the UK tick, Ixodes ricinus, is causing AGS red meat allergy in UK residents.

The patient's history of tick exposure and several bites builds up an immune response to tick saliva. Patients present with urticaria 4–6 hours after eating red meat, and the diagnosis is confirmed with specific immunoglobulin E (IgE) serology.

Alpha-gal Syndrome Treatment and Prevention

The best way to prevent contracting AGS is to prevent tick bites, especially if you are someone who enjoys being outdoors.

If you have experienced a tick bite, prevention includes prompt tick removal without squeezing the tick, which prevents the injection of tick saliva antigen into genetically susceptible individuals.

People who are leaving with AGS should be managed under the care of an allergist or other healthcare provider, and patients with AGS should stop eating meat from mammals, such as beef, pork, lamb, venison, or rabbit. However, not all patients with AGS have reactions to every product containing alpha-gal.

Furthermore, treatment is limited to antihistamines and EpiPens, and avoiding meat products. Several medicines can precipitate an acute anaphylaxis.

Rob, a Person Living With Alpha-Gal Syndrome

Rob, from Georgia, shared his experience with Alpha-gal Syndrome.

He recalled, 'I remember waking up in the middle of the night feeling really strange. I got up and felt lightheaded, like I was going to fall over. And then, eventually, I was covered in hives.'

He explained that he felt scared and frustrated, not understanding what was happening to his body—at least until he visited another allergist and received a diagnosis.

'She was like, "Well, there's one thing it could be, but you would have had to have been bitten by a tick." Of course, I thought, "Alright, I get bitten by ticks all the time,"' Rob said.

Rob, who camps frequently and spends a lot of time in the woods, added, 'I'm always pulling ticks off myself.'

He admitted he had never heard of the syndrome before. He also noted that lone star ticks can be easily identified, 'They have a lighter mark on their back.'

'It's not like other common food allergies, where you eat something and react almost immediately,' he explained. 'The reaction is delayed after eating, which made it really hard to diagnose because I wasn't associating my meal with the reaction.'

'Turns out the only way to manage it was to avoid meat altogether. Specifically, I can't eat red meat,' Rob said.