Effect of flushing on the detachment of biofilms attached to the walls of metal pipes in water distribution systems

Liu, Jingqing; Luo, Zhifeng; Liu, Ke; Zhang, Yifu; Peng, Huan; Hu, Baolan; Ren, Hongxing; Zhou, Xiaoqing; Qiu, Shangde; He, Xiaofang; Bastani, Hamid; Lou, Liping

doi:10.1631/jzus.a1600316

Cited by 22 publications

(22 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Specifically, we found (i) statistically significant differences in disinfectant efficacy among disinfectants, (ii) similar performance of hydrogen peroxide and sodium hypochlorite-based products against S. aureus and P. aeruginosa biofilms, and iii) significantly higher bactericidal efficacy of quaternary ammonium-based products against S. aureus than P. aeruginosa . Bacterial biofilms are common on a wide range of surfaces made of different materials and have been reported to be present in drains, metal pipes [10], sanitizing bottles, trolleys and clipboards [23] thus are potential sources of HAIs.…”

Section: Discussionmentioning

confidence: 99%

“…Within healthcare facilities, Staphylococcus aureus and Pseudomonas aeruginosa are amongst the most problematic pathogens [8] with S. aureus being the second most common pathogen that caused HAIs [9]. These pathogens grow on hard non-porous surfaces such as metal pipes and floor drains [10] and develop an extracellular polymeric matrix that protects the cells from adverse conditions [4, 11]. It has also been shown that the biofilm matrix enhances tolerance to disinfectants by encasing the underlying cells [12, 13] and by limiting diffusion of disinfectants into the biofilm matrix [14].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Hydrogen peroxide and sodium hypochlorite disinfectants are more effective against Staphylococcus aureus and Pseudomonas aeruginosa biofilms than quaternary ammonium compounds

Lineback

Nkemngong

et al. 2018

Antimicrob Resist Infect Control

115

View full text Add to dashboard Cite

BackgroundAntimicrobial disinfectants are used as primary treatment options against pathogens on surfaces in healthcare facilities to help prevent healthcare associated infections (HAIs). On many surfaces, pathogenic microorganisms exist as biofilms and form an extracellular matrix that protects them from the antimicrobial effects of disinfectants. Disinfectants are used as all-purpose antimicrobials though very few specifically make biofilm efficacy claims. The objective of this study was to evaluate the efficacy of eight registered disinfectants (six registered by the Environmental Protection Agency and two products registered in by the European Chemical Agency) with general bactericidal claims, but currently no biofilm efficacy claims, against Staphylococcus aureus ATTC-6538 and Pseudomonas aeruginosa ATCC-15442 biofilms. We hypothesized that hydrogen peroxide and sodium hypochlorite disinfectant products would be more effective than quaternary ammonium chlorides.MethodsThis study tested the bactericidal efficacy of eight registered disinfectant products against S. aureus ATCC-6538 and P. aeruginosa ATCC-15442 grown on glass coupons using a Center for Disease Control (CDC) biofilm reactor and EPA MLB SOP MB-19. Bactericidal efficacy was determined after treating coupons with disinfectants following standard EPA MLB SOP MB-20.ResultsOverall, sodium hypochlorite and hydrogen peroxide disinfectants had significantly higher bactericidal efficacies than quaternary ammonium chloride disinfectants. We also found that all tested disinfectants except for quaternary ammonium chloride disinfectants met and exceeded the EPA standard for bactericidal efficacy against biofilms.ConclusionIn general, bactericidal efficacy against biofilms differed by active ingredient. The efficacies of sodium hypochlorite and hydrogen peroxide disinfectants did not vary between strains, but there were significant differences between strains treated with quaternary ammonium chloride disinfectants.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Hydrogen peroxide and sodium hypochlorite disinfectants are more effective against Staphylococcus aureus and Pseudomonas aeruginosa biofilms than quaternary ammonium compounds

Lineback

Nkemngong

et al. 2018

Antimicrob Resist Infect Control

115

View full text Add to dashboard Cite

show abstract

“…and methicillin-resistant Staphylococcus aureus (MRSA) [5,6,7]. In particular, S. aureus and P. aeruginosa are hazardous microorganisms, able to grow on hard non-porous surfaces (e.g., metal pipes and floor drains) and develop biofilms that protect them from adverse conditions [8,9]. Their resistance to various antimicrobial substances can compromise patients’ therapeutic protocol [10], increasing the need to improve disinfection procedures in healthcare settings [11,12].…”

Section: Introductionmentioning

confidence: 99%

Study on the In Vitro Activity of Five Disinfectants against Nosocomial Bacteria

Montagna

Triggiano

Barbuti

et al. 2019

IJERPH

View full text Add to dashboard Cite

Nosocomial infections cause significant morbidity and mortality worldwide, and the pathogenic organisms responsible for such infections can develop resistance to antimicrobial agents. Understanding the activity of disinfectants against clinical and environmental bacterial isolates is therefore crucial. We analysed the in vitro activity of five antimicrobial products (phenolic compounds, didecyldimethylammonium chloride (DDAC), sodium hypochlorite, isopropanol + ammonium compounds (IACs), hydrogen peroxide) against 187 bacterial strains comprising clinical isolates, as well as 30 environmental isolates of Pseudomonas aeruginosa from hospital water samples. Disk diffusion assays were employed to assess antimicrobial activity. Hydrogen peroxide was significantly more active (p < 0.0001) than the other disinfectants against all P. aeruginosa, Klebsiella pneumoniae, Enterococcus faecalis and Staphylococcus aureus strains. It was also the only disinfectant with activity against both clinical and environmental strains of P. aeruginosa. DDAC and IAC-based disinfectants were ineffective against Gram-negative strains, but showed significant activity (particularly IACs, p < 0.0001) against the Gram-positive strains. Compared with IACs, DDAC was significantly more active on E. faecalis and less active on S. aureus (p < 0.0001). Sodium hypochlorite and phenol compounds, by contrast, were inactive against all bacterial strains. The development of disinfection procedures that are effective against all microorganisms is essential for limiting the spread of nosocomial infections.

show abstract

“…As the number of flushing/flow events on the day of sampling increased there was an initial increase in total heterotrophic bacteria observed. This could possibly be attributed to biofilm detachment caused by sheering [18]. However, after five flushing events there was a decline in total heterotrophic bacteria, which plateaued after around 10 flushing events (Figure 1).…”

Section: Resultsmentioning

confidence: 99%

Real-Time Continuous Surveillance of Temperature and Flow Events Presents a Novel Monitoring Approach for Hospital and Healthcare Water Distribution Systems

Whiley

Hinds²,

Xi³

et al. 2019

IJERPH

View full text Add to dashboard Cite

Within hospitals and healthcare facilities opportunistic premise plumbing pathogens (OPPPs) are a major and preventable cause of healthcare-acquired infections. This study presents a novel approach for monitoring building water quality using real-time surveillance of parameters measured at thermostatic mixing valves (TMVs) across a hospital water distribution system. Temperature was measured continuously in real-time at the outlet of 220 TMVs located across a hospital over a three-year period and analysis of this temperature data was used to identify flow events. This real-time temperature and flow information was then compared with microbial water quality. Water samples were collected randomly from faucets over the three-year period. These were tested for total heterotrophic bacteria, Legionella spp. and L. pneumophila. A statistically significant association with total heterotrophic bacteria concentrations and the number of flow events seven days prior (rs[865] = −0.188, p < 0.01) and three days prior to sampling (rs[865] = −0.151, p < 0.01) was observed, with decreased heterotrophic bacteria linked to increased flushing events. Only four samples were positive for Legionella and statistical associations could not be determined; however, the environmental conditions for these four samples were associated with higher heterotrophic counts. This study validated a simple and effective remote monitoring approach to identifying changes in water quality and flagging high risk situations in real-time. This provides a complementary surveillance strategy that overcomes the time delay associated with microbial culture results. Future research is needed to explore the use of this monitoring approach as an indicator for different opportunistic pathogens.

show abstract

Effect of flushing on the detachment of biofilms attached to the walls of metal pipes in water distribution systems

Cited by 22 publications

References 34 publications

Hydrogen peroxide and sodium hypochlorite disinfectants are more effective against Staphylococcus aureus and Pseudomonas aeruginosa biofilms than quaternary ammonium compounds

Hydrogen peroxide and sodium hypochlorite disinfectants are more effective against Staphylococcus aureus and Pseudomonas aeruginosa biofilms than quaternary ammonium compounds

Study on the In Vitro Activity of Five Disinfectants against Nosocomial Bacteria

Real-Time Continuous Surveillance of Temperature and Flow Events Presents a Novel Monitoring Approach for Hospital and Healthcare Water Distribution Systems

Contact Info

Product

Resources

About