This is really concerning for those of us on immunosuppressants. It was on MSNBC. Mycobacterium avium is found in soil and can be gotten "from the dirt under your finger nails" from gardening, etc. It shows up as a positive on a TB skin test and behaves like TB. It is treated like TB, with isoniazid or other antiTB drugs. Actually, they think I probably had this, mycobacterium avium.
http://today.msnbc.msn.com/id/32845180/ns/health-infectious_diseases/
I have well water and wonder if it is safe. uv sterilization, reverse osmosis,and possibly other filtration methods, maybe an iron filter or other type might be effective, not sure.
There are bacteria everywhere .....this is another media hype.
Bill