Impact of Electronic Faucets and Water Quality on the Occurrence ofPseudomonas aeruginosain Water: A Multi-Hospital Study

Abstract

OBJECTIVETo comparePseudomonas aeruginosaprevalence in electronic and manual faucets and assess the influence of connecting pipes and water quality.SETTINGFaucets in 4 healthcare centers in Quebec, Canada.METHODSWater samples from 105 electronic, 90 manual, and 14 foot-operated faucets were analyzed forP. aeruginosaby culture and enzymatic detection, and swab samples from drains and aerators were analyzed by culture. Copper and residual chlorine concentrations, temperature, and flow rate were measured.P. aeruginosaconcentrations were analyzed in 4 consecutive volumes of cold water and a laboratory study was conducted on copper pipes and flexible hoses.RESULTSP. aeruginosacontamination was found in drains more frequently (51%) than in aerators (1%) or water (culture: 4%, enzyme detection: 16%). Prevalence in water samples was comparable between manual (14%) and 2 types of electronic faucets (16%) while higher for foot-operated faucets (29%). However, type 2 electronic faucets were more often contaminated (31%) than type 1 (14%), suggesting that faucet architecture and mitigated volume (30 mL vs 10 mL) influenceP. aeruginosagrowth. Concentrations were 100 times higher in the first 250 mL than after flushing. Flexible hoses were more favorable toP. aeruginosagrowth than copper and a temperature of 40°C led to higher counts.CONCLUSIONSThe types of faucets and connecting pipes, flow rate, and water quality are important parameters influencing the prevalence and the concentrations ofP. aeruginosain faucets. High concentrations ofP. aeruginosain the first 250 mL suggest increased risk of exposure when using the first flush.Infect Control Hosp Epidemiol 2014;00(0): 1–9