That's my biggest concern is reinfection as well. Things I've done: I increased my water heater temperature and installed an ultrafiltration undersink sytsem at my kitchen sink for drinking water and washing fruits and vegetables. I also installed a new shower head (one where the shower head drains), though I'm thinking about getting a filter for that as well. I don't take hot showers, which I miss. I just haven't been able to find a filter for shower. I also buy spring water when out of town. Spring water has a low to zero NTM count. When I was at NJH, I was tested for reflux and whether or not I'm prone to aspirating food. These are very important tests to get-if you haven't. Fortunately, I wasn't a high risk but there's no such thing as no risk, when it comes to aspirating food/drink. I was given swallowing exercises, which I did and now do periodically. Also, be aware of water vapor-washing dishes, opening a hot dishwasher, and the hot showers. The paper that pacathy posted is a good resource. I religiously nebulize with 7% saline 2x/day with huff coughs. I sure would like to reduce someday to 1/day, but it helps keep my lungs clear. I also always have a mask handy if needed. I'm happy to hear you are tolerating your meds and you are especially lucky to be able to take Azithromycin, it is the best gun there is for MAC.