IBD is a serious bacterial disease that boas can carry for years with no symptoms, and can easily pass along to ball pythons, usually wiping out ball pythons fairly quickly with no notice. Before this starts an argument, I am basing this 100% on what I have read and talked to other people about, I do not have personal experience with IBD and hope to keep it that way. I own both balls and a boa and neither have ever been in contact with each other and I am very careful with cross contamination.
Here's just one of the hundreds of articles on IBD....
Even though it's fairly rare, still not worth finding out the hard way to me...