Allergic reactions to “alpha-gal” – a sugar found in the blood of many mammals – are on the rise, and it’s a phenomenon that has captured much recent media attention. Although alpha-gal in meat usually poses no problems for humans, people can become sensitised to the carbohydrate after being bitten by a tick. Unlike other food allergies, this condition can cause a delayed onset of anaphylactic symptoms three to six hours after the ingestion of mammalian meat food products such as beef, pork or lamb.
It appears that wherever ticks bite people (which is everywhere other than the Arctic and Antarctic), alpha-gal allergy has been recorded. Professor Sheryl van Nunen, Director of the Sydney-based Tick-induced Allergies Research and Awareness (TiARA) Centre, came across her first case of the allergy in 1987. By 2003, she had seen at least 70 further cases in Australia and numbers here are now in the hundreds. In the US, there have now been about 5,000 known cases of the allergy, up from 3,500 cases just two years ago.
Some people are said to be so sensitive to alpha-gal they react to several mammal products, particularly their milks and gelatine. Any product derived from mammals may cause allergic reactions, making avoidance very difficult as the allergen may be found in a wide range of agents used in medical treatments, as well as in foods. Reactions can vary from stomach problems such as cramps, nausea, vomiting and diarrhoea, as well as runny nose, sneezing, headaches, asthma, rash and hives. In the worst cases, it can invoke severe anaphylactic reactions.
In June 2018, the U.S. National Institute of Health (NIH) hosted an invitation-only one-day IgE-mediated Meat Allergy Workshop to hear from key researchers and physicians experienced in managing patients with alpha-gal allergy. This was the first step in the NIH possibly committing to a research program to better understand the condition.
Media write-ups about the rise of meat allergies can be found at: