An Assessment of Legionella pneumophila and Mycobacterium avium in Residential and Commercial Structures

摘要

Legionella pneumophila and Mycobacterium avium are water-borne pathogens. I investigated the occurrence of L. pneumophila and M. avium in potable water at residential and commercial structures. This was performed to understand which locality may pose the highest risk for infection based on the occurrence and observed concentrations of these microorganisms in potable water. Between the years of 2009-2014, potable water from 136 taps (62 residential and 74 commercial) across the United States were monitored for the presence of these microorganisms. Water was collected at three independent time points for a total of 408 samples. In general, three liters of water were filtered through a polycarbonate membrane. The DNA was extracted from the captured material. Quantitative Polymerase Chain Reaction (qPCR) was then used to detect and measure the concentrations of these microorganisms in the final extract. Both microorganisms were detected in the potable water from both residential and commercial buildings. Of the 62 taps that were located in a residence, 27% were positive for L. pneumophila, and 23% were positive for M. avium. The 74 taps that were located in a building, 41% and 39% were positive for M. avium and L. pneumophila, respectively. Longitudinal data revealed the L. pneumophila persisted for longer lengths of time in water from residences and at higher concentrations (avg: 10,830 genomic targets/L, Max: 82,250 genomic targets/L). For M. avium, higher concentrations (avg: 715 genomic targets/L, Max: 148,270 genomic targets/L) were detected in buildings. These findings will help craft a better understanding as to possible exposure routes to these microorganisms that are most relevant for infection to occur. Disclaimer: The views expressed in this abstract are those of the authors and do not necessarily reflect the views or policies of the U.S. EPA. Mention of trade names or commercial products does not constitute endorsement or recommendation for use.