What is mammalian meat allergy?
Mammalian Meat Allergy (MMA) is an allergy to mammalian meats or products made from mammalian meats. A person may develop MMA after they have been previously bitten by a tick. The connection between tick bites and developing MMA was discovered by Sydney clinical immunology/allergy specialist, Associate Professor Sheryl van Nunen OAM. A carbohydrate called alpha-galactose (alpha-gal) has found to be connected with the development of MMA.
MMA can develop weeks (or longer) after a tick bite. Some people who develop MMA are known to have had allergic reactions to ticks (such as a large local reaction or anaphylaxis). Other people, who did not have an allergic reaction when they were bitten by a tick, still go on to develop MMA .
A person with MMA can experience a mild or moderate allergic reaction or severe allergic reaction (anaphylaxis).
What are mammalian meats?
Mammals are warm blooded animals that produce milk to feed their young and have a unique jaw structure.
Mammalian meats include but are not limited to:
- Beef
- Pork
- Lamb
- Kangaroo
- Goat
- Horse
- Venison
- Exotic animals including whales and dolphins.
What is not mammalian meat?
- Poultry – such as chicken, turkey, duck, and quail, as these meats come from birds.
- Seafood – includes fish, crustacea and molluscs.
- Crocodile – is a reptile.
Examples of mammalian meat products
- Gelatin – Gelling/Setting agents made from mammals.
- Fats – Tallow, suet, lard.
Why is MMA different to other food allergy?
Unlike immediate type food allergy, which is caused by the protein in the food, the mammalian meat allergen (thing that causes the allergic reaction) is a carbohydrate called alpha-galactose (alpha-gal). Alpha-gal is found in meat from all mammals except humans, great apes and old world monkeys. It is also found in the saliva of ticks.
Most allergic reactions to food happen within a few minutes to 2 hours of eating the allergen but in MMA the reaction is delayed, often occurring 2-6 hours after eating mammalian meat. Many people with MMA will wake up in the night with symptoms of an allergic reaction after having eaten dinner containing mammalian meat hours earlier.
Another difference is that MMA can get better. If ticks are avoided and a person with MMA does not get bitten again, levels of allergy antibody to alpha gal can lower over 12 to 18 months. Some people with MMA can return to eating mammalian meat after 3–4 years if they do not get any further tick bites. Further tick bites can increase the level of allergy antibody to alpha gal in a person with MMA.
https://allergyfacts.org.au/allergy/mammalian-meat/
