If red meat gives you trouble even though you haven’t been bitten by a tick, cats may be the cause. During their research on alpha-gal allergy, Scott Commins and Thomas Platts-Mills documented the first U.S. cases of pork-cat syndrome: an allergy to pork caused by sensitization to cats.

“Pork-cat is really unusual,” Commins says. “It was Europeans who described it, and we thought that there wasn’t any of this in the U.S. But there were some patients who were telling us, ‘I eat beef okay, but I can’t eat pork and I have reactions pretty quickly.’ Most of them were negative for alpha-gal, so we were pretty confused. We started wondering if it fit with the pork-cat syndrome. We did tests and found exactly that. Pork-cat is more common than previously thought, but we still don’t see much of it.”

Almost all people with the condition are cat owners, and many have multiple cats. Some develop an allergic response to cat serum albumin (protein made by a cat’s liver) that cross-reacts with albumin in pork when someone consumes it, and can lead to severe or even fatal allergic reactions when pork is consumed.

Marta Zaraska