Last I heard there wasn’t a scientific answer for why some people developed food allergies like a red meat allergy after a tick based infection so that theory would be pure speculation on the doctor’s part. I’m not a doctor and this information may be old so take it with a grain of salt
The allergy is specifically to galactose-alpha-1,3-galactose, a very common carbohydrate that occurs in both the meat of domesticated ungulates and the saliva of ticks, but which is not produced by primates. The idea is that tick bites initiate an exaggerated immune response, but more study is required.
