You'd be surprised the number of Demodex cases we see at animal shelters (and vet clinics) that are past the treatable stage.

Besides, if there is a large increase in the IBD incidence rates, there will be more effort placed on getting it under control medically. There are already groups that have started work on it...I'm sure they didn't have a cure for Demodex when it first was isolated either.

Anoter suitable example would be Streptococcus pyrogenes that lives on our skin. Most of us have no issue with it: we get a cut, we heal. Most of us even have the pathogenic form living in our throats. It's only certain people or certain environmental triggers that cause Strep Throat or Necrotizing Fasciitis; otherwise people aren't running for the hills over these things.

Either way, we will have to wait until it happens to react to it