Nontuberculous mycobacteria from household plumbing of patients with nontuberculous mycobacteria disease.

To determine whether plumbing could be a source of nontuberculous mycobacteria (NTM) infection, during 2007-2009 I isolated NTM from samples from household water systems of NTM patients. Samples from 22/37 (59%) households and 109/394 (28%) total samples yielded NTM. Seventeen (46%) of the 37 households yielded ≥1 Mycobacterium spp. isolate of the same species as that found in the patient; in 7 of those households, the patient isolate and 1 plumbing isolate exhibited the same repetitive sequence-based PCR DNA fingerprint. Households with water heater temperatures ≤125 degrees C (≤50 degrees C) were significantly more likely to harbor NTM compared with households with hot water temperatures ≥130 degrees F (≥55 degrees C) (p = 0.0107). Although households with water from public or private water systems serving multiple households were more likely to have NTM (19/27, 70%) compared with households with a well providing water to only 1 household (5/12, 42%), that difference was not significant (p = 0.1532).