Yes, I think it depends on what strain. Anna had Myco Bacterium Avium (SP?), aka-MAC. From what I understood with that is, usually it is only found in patients with compromised immune systems, such as Anna's. They found it two months after a bought of A4 rejection, 18 months post transplant. It did not prevent her from traveling, in fact they called her as she was boarding a plane back to NE from a tx clinic appt. in CA. For her, and I guess this particular strain, they put her on 1000mg of Ethambutol and 300mg of Mycobutin three times a week. Apparently these are two very old drugs that have been in successful use for many many years. She was told when she cultured three consecutive negatives, she would then be on these two meds. for one year from the third cultured negative.
So has been our experience with MAC and how the transplant doctors at Stanford treated it. Anna is currently listed for a second tx at Cleveland Clinic and they agreed with the treatment that she went through. We were pleased to have two great hospitals agree on a treatment process.
From what I have read up on how the heck she even caught MAC and from what the doctors told us. Being exposed is almost unavoidable. The concern comes when you have a compromised immune system. Not to scare you away from taking nice hot showers, but hot water heaters are a culpret. Really its the age of the hot water heaters, sedement, rust, how the water sits there waiting to be used. The docs said there was nothing you can really do to prevent it and they wouldn't suggest avoiding taking a nice hot shower or washing your face. Life must go on. They were not too concerned and they were dealing with a transplant patient. They certainly put our minds at ease. I think if the possibility of contracting MAC was of great concern then it would have been a subject on one of the many pages of instructions post transplant, like wearing at least a P95 mask in the hospital and around areas where they were doing construction and if you like to garden, but it wasn't.
I tend to ramble sometimes, sorry. When you find out what strain of Mycobacteri you have I hope this helps.