Once you have over 10 grand in animals in your collection, if you didn't think about it seriously before, you do then.
Ultra strict quarantine is a necessity. This fatal disease can and has devastated entire collections due to one miss-step with an infected, mite-ridden animal.
Always quarantine new arrivals, no matter WHERE they came from--but animals from wholesale facilities or 'flippers' should be scrutinized particularly carefully.
How common this disease is, is actually unknown, because most breeders who have an animal die of it, even in quarantine, will not make a public announcement about it. Paranoia runs SO high, they could lose sales due to simply having had the disease within a mile of their collection. It may actually be more common than is realized, as a result of that.
Being paranoid isn't a bad thing, when it comes to these diseases (IBD is one of several dangerous viral diseases that can kill ball pythons).