I mean, it's probably not a particularly fun experience to only find out that you have this allergy after you almost fucking die eight hours after getting a vaccine with trace amounts of alpha-gal in it, in severe cases.
As the disease rises in prominence, I reckon we'll start to see at-home tests. I certainly hope that happens.
If it would only be meat, sure. Unpleasant but manageable. But the animal products can be a problem. They not only put you very close to the most hard-core of vegans diet plan, they additionally mess with medical treatment available to you.