Well if your snake is already 6 years old, you really shouldn't have much to worry about. I just put my Brazilian rainbow in the room with my pythons...it's been 4 months of quarantine. Then again i get all my snakes from reputable people and treat everything as if its a surgical procedure with cleanliness.
Case in point, i don't think your snake has IBD unless he had a sleepover with a diseased boa recently.