Details

Autor(en) / Beteiligte

• Pierre, David
• Baron, Julianne L
• Ma, Xiao
• Sidari, 3rd, Frank P
• Wagener, Marilyn M
• Stout, Janet E

Titel

Water Quality as a Predictor of Legionella Positivity of Building Water Systems

Ist Teil von

• Pathogens (Basel), 2019-12, Vol.8 (4), p.295

Ort / Verlag

Switzerland: MDPI AG

Erscheinungsjahr

2019

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• Testing drinking water systems for the presence of colonization is a proactive approach to assess and reduce the risk of Legionnaires' disease. Previous studies suggest that there may be a link between positivity in the hot water return line or certain water quality parameters (temperature, free chlorine residual, etc.) with distal site positivity. It has been suggested that these measurements could be used as a surrogate for testing for in building water systems. We evaluated the relationship between hot water return line positivity and other water quality parameters and colonization in premise plumbing systems by testing 269 samples from domestic cold and hot water samples in 28 buildings. The hot water return line positivity and distal site positivity only demonstrated a 77.8% concordance rate. Hot water return line positivity compared to distal site positivity had a sensitivity of 55% and a specificity of 96%. There was poor correlation and a low positive predictive value between the hot water return line and distal outlet positivity. There was no correlation between distal site positivity and total bacteria (heterotrophic plate count), pH, free chlorine, calcium, magnesium, zinc, manganese, copper, temperature, total organic carbon, or incoming cold-water chlorine concentration. These findings suggest that hot water return line positivity and other water quality parameters are not predictive of distal site positivity and should not be used alone to determine the building's colonization rate and effectiveness of water management programs.