So then I'd also like to know what fraction of captive pythons are also "asymptomatic" carriers.

... but leaving that aside, and still assuming IBD originated with boas, it also means that any imported boas are pretty likely to have it.

We need a better blood test. Resistance from the boa community, yeah, I know, but this could turn out to just be something boas and boa owners have to live with, like toxoplasmosis and FIV in cats.