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					A Fresh and Appropriate
      Approach to
  Hygienic Cleaning of
     Environmental
       Surfaces
    Public attitudes towards bacterial
     resistance: a qualitative study
• Although members of the public can contribute
  to containing bacterial resistance, most do
  not feel that they have a personal role in either
  the problem or its solution. Campaigns should
  identify bacterial resistance as both a hospital
  and a community problem that individuals have
  the power to influence through specific actions

•   April 21, 2007 Journal of Antimicrobial Chemotherapy,
      Current Practices

•Surfactant based cleaning and
disinfecting contribution to microbial
resistance to biocides and antibiotics.


This discussion presents a fresh
approach to address these
problems…
            Current Practices

•    There is growing evidence today that
    leaving toxic surfactant detergent
    disinfectant residues on
    environmental surfaces and in our
    waste water contributes to
    development of bacterial resistance to
    biocides and antibiotics.
Adaptive Resistance of Salmonella enterica
  Serovar Enteritidis Biofilms Exposed to
         Benzalkonium Chloride

• Resistance of biofilm pathogens following
  exposure to either continuous (1 μg ml−1) or
  intermittent (10 μg ml−1 for 10 min daily)
  benzalkonium chloride (BC) was examined.
• Biofilm pathogens that adapted to BC
  exposure over 144-hours could survive a
  normally lethal BC challenge (500 μg ml−1
  for 10 min) and then regrow

         Antimicrobial Agents Chemother. 2006 November; 50(11): 3588–3596.
•There are concerns that the inappropriate use
(inadequate concentrations, insufficient cleaning
before the application, or the presence of sub lethal
residual disinfectants following cleaning) of these
biocidal compounds may contribute to the spread of
bacterial resistance to these compounds, as well as
cross-resistance to certain therapeutic antibiotics.
        Susceptibility of multiresistant
    Pseudomonas aeruginosa isolates to a
   hospital disinfectant and molecular typing

• We found isolates with reduced susceptibility
  to the QAC disinfectant.
• Resistance to quaternary ammonium may co-
  select for antibiotic resistance via class 1
  integrons and vice-versa.


   Mem. Inst. Oswaldo Cruz vol.100 no.5 Rio de Janeiro Aug. 2005
Prolonged treatment of Salmonella enterica
serovar Typhimurium with commercial disinfectants
selects for multiple antibiotic resistance


• Our work demonstrates that subinhibitory
  concentrations of disinfectants, which might occur
  during poor disinfection and cleaning procedures, can
  lead to selection of strains with reduced susceptibility,
  or even resistance to antibiotics.
• These effects were more pronounced with a quaternary
  ammonium based biocide and with the use of high
  concentrations of triclosan.


 Journal of Antimicrobial Chemotherapy (2007) 60, 947–955Advance Access publication 13 September 2007
Genomics of IncP-1 plasmids isolated from wastewater
                  treatment plants
 • Based on genomic analysis of IncP-1 resistance
   plasmids:
    – These plasmids encode resistance to clinically relevant
      antimicrobial drug classes including tetracyclines,
      aminoglycosides, macrolides, β-lactams, chloramphenicol,
      sulphonamides and trimethoprim.
    – Additional genes were identified that encode resistance to heavy
      metals (mercury and chromate) or quaternary ammonium
      compounds (used in detergents).
    – Integrons were frequently found on IncP-1 plasmids
        • ‘Since these elements play an important role in the acquisition and
          exchange of genes encoding resistance to antibiotics and QACs,
          their presence on conjugative, broad-host-range plasmids is
          worrying. Indeed, linkage of genes encoding both antibiotic and
          QAC resistance allows for selection of drug resistance
          determinants by disinfectants “

                            Microbiology reviews July 2007
Disinfectant-resistant bacteria in Buenos
     Aires city hospital wastewater
• Disinfectants present in the hospital wastewater may
  act as selective pressure for the retention of the
  plasmids that often contain the genes for resistance to
  numerous antibiotics (14,22,23,26). It is generally
  agreed that the selection and dissemination of
  resistant bacteria in nature should be avoided in order
  to ensure effective treatment against infectious
  diseases in humans and maintain an ecological
  balance that favors the predominance of a susceptible
  bacterial flora in nature. The indiscriminate use of
  antimicrobial agents may disrupt the microbial
  balance in favor of resistance bacteria. In particular,
  wastewater from hospital plants could play a role in
  the selection of resistance bacteria in sewage (6,16).
     JAC Advance Access published online on January 28, 2008

    Journal of Antimicrobial Chemotherapy, doi:10.1093/jac/dkm520

• Objectives: To detect genes conferring resistance to biguanides,
  quaternary ammonium compounds, β-lactams and fluoroquinolones in
  clinical methicillin-resistant Staphylococcus aureus (MRSA) and to
  demonstrate whether reduced susceptibility is spread clonally and if
  the presence of any of the detected genes links to a specific epidemic
  MRSA. Finally, to identify if exposure to chlorhexidine may cause
  reduced susceptibility to antibiotics and chlorhexidine.

• Conclusions: In our study, isolates resembling PFGE type EMRSA-16
  harboured more biocide resistance genes than other types. The
  observed reduction in susceptibility of clinical isolates to chlorhexidine
  may mean that a selective pressure is being exerted by residues in the
  clinical environment, and highlights the importance of efficacy testing
  on clinical strains and good infection control practices. The
  development of reduced microbial susceptibility to biocides
  represents a serious cause for concern in the clinical environment
              Mem. Inst. Oswaldo
            Cruz vol.102 no.4 Rio de
               Janeiro June 2007


• A total of 74 methicillin-resistant Staphylococcus
  aureus (MRSA) strains isolated from three
  government hospitals in 2002 and 2003 were
  examined concerning the distribution of qacA/B gene,
  which is the determinant of resistance to quaternary
  ammonium compounds largely employed in hospital
  disinfection. By polymerase chain reaction the qacA/B
  gene was found in 80% of the isolates, which is a
  significant result considering it is the first time that
  qacA/B gene is being reported for Brazilian MRSA
  strains and it is presented at a high rate.
      The association between biocide tolerance and the presence or
      absence of qac genes among hospital-acquired and community-
                         acquired MRSA isolates




•      In this study, Hospital Acquired MRSA isolates displayed
    significantly higher MBC to a quat than MSSA isolates. This
    would suggest that there is a correlation between antibiotic
    resistance and biocide tolerance.

•     Although a definitive link between antibiotic and biocide
    resistance has not been established, it has been observed that
    the MBC of QACs was significantly higher for clinical isolates of
    MRSA than MSSA.

•      Our study reinforces this link in S. aureus and the issue of
    biocide–antibiotic co-resistance should no longer be ignored.
    The association between biocide tolerance and the presence or
    absence of qac genes among hospital-acquired and community-
                       acquired MRSA isolates



• The continued exposure of bacteria to residual levels of
  biocides in the hospital environment is causing concern.

•       The presence of qac genes in the clinical S. aureus
     population and their ability to develop increased tolerance
     highlights the importance of effective and rigorous infection
     cleaning and infection control strategies.




•    Journal of Antimicrobial Chemotherapy Advance Access published November 2, 2007
        Importance of environmental
       decontamination: a critical view
• “ The level of evidence supporting different disinfection and
  cleaning procedures performed in healthcare settings
  worldwide is low”.

• “It must be kept in mind that the effect of surface disinfection is
  only transient, microbial contamination will have reached its
  former level within a few hours.”

• “With respect to environmental surfaces, the final assessment
  of whether use of disinfectants, rather than detergents alone,
  to reduce nosocomial infection rates in different clinical
  settings still awaits conclusive study.”



        Journal of Hospital Infection (2007) 65(S2) 55–57
        Importance of environmental
       decontamination: a critical view
•      As with proper cleaning procedures,
    targeted surface disinfection is indispensable
    in modern hospitals. However, disinfectants
    may be hazardous to personnel and patients,
    as well as the environment, and require
    special safety precautions. An uncritical use
    of biocides, especially in low concentrations,
    may lead to the development of resistance.




       Journal of Hospital Infection (2007) 65(S2) 55–57
                          MRSA

• Cleaning surfaces with detergent-based
  cleaners or Environmental Protection
  Agency (EPA)-registered disinfectants is
  effective at removing MRSA from the
  environment.

•   CDC MRSA in Schools
          Current Practices
• The current practice of leaving toxic
  residues on environmental surfaces
  after cleaning has not reduced the
  potential spread of pathogens from
  environmental surfaces.
• Antimicrobial surfactants residues after
  drying on surfaces are quickly reduced
  to sub-inhibitory concentrations.
 Induction of multiple antibiotic resistance by
    benzene and benzene- derived active
                 compounds
• Objectives: To determine the potential of active
  compounds (ACs) present in commonly used
  analgesics/antiseptics and cleaning agents
  (detergents and disinfectants) to induce multiple
  antibiotic resistance (MAR) in Bacteroides
  fragilis.



      Journal of Antimicrobial Chemotherapy Advance Access published September 20, 2007
          Tested inorganic compounds
 (sodium hypochlorite, ammonium hydroxide and
hydrogen peroxide) were essentially non-inducing.
    Toxicity of anionic detergents determined by Saccharomyces
                    cerevisiae microarray analysis
 Sophon Sirisattha, Yuko Momose, Emiko Kitagawa, Hitoshi Iwahashi*




The mRNA expression profiles suggest
that LAS and SDS cause damage to
membranes and alterations in carbon
metabolism, and induce the oxidative
stress response. We also found that LAS
and SDS induce the pleiotropic drug-
resistance network,
Some studies have demonstrated
that these residues can increase
  the persistence of C. Difficile
  In vitro effects of environmental
disinfectants on spore formation (ii)




  Fawley WN, et al. Infect Control Hosp Epidemiol 2007;28:920-5.
            Antimicrobial Products In The Home
             Canadian Pediatric Society, 2006

      •Where appropriate, alcohol, bleach or peroxidase-
      based agents are preferred because they dissipate
      readily and are less likely to exert prolonged
      antimicrobial pressure. Agents such as triclosan,
      chlorhexidine and quaternary ammonium
      compounds exert more prolonged antimicrobial
      pressure.




Pediatric and Child Health 2006;11:169-173
       Surfactants are Toxic
• Surfactants used in cleaning and
  disinfecting of environmental surfaces are
  all rated as toxic to aquatic life.
• Surfactants used in cleaning of
  environmental surfaces all have toxic
  effects on microbial populations
  bactericidal and/or bacteriostatic.
• Surfactant toxic effects on microbial
  populations contributes to bacterial
  adaptation and resistance development.
   Journal of Antimicrobial Agents
Volume 28, Issue 6, December 2006
     Toxicity of anionic detergents determined by Saccharomyces
                     cerevisiae microarray analysis
  Sophon Sirisattha, Yuko Momose, Emiko Kitagawa, Hitoshi Iwahashi*




• The concentrations of LAS and SDS that
  cause growth inhibition were studied after
  screening of the various concentrations of
  LAS and SDS that affect cellular growth.
  The growth curves showed that, at 0.02%
  LAS and 0.01% SDS, there was a 50%
  decrease in the specific growth (IC50)
  after a 2 h treatment.
International Symposium on Environmental Biotechnology 2006, Leipzig, Germany
                                    288
 Effects of detergent shock loads on anaerobic granular sludge morphology
                         and methanogenic activity




After exposure to 0.30 g/L of detergent the
COD removal efficiency decreased
drastically.
  Effect of Surfactants on Soil Bacteria
         by LUDWIG HARTMANN
  Head, Laboratory o] Engineering-Biology
Technische H ochschule Karlsruhe, Germany
  Consumption of Surfactants


• In 1998 the estimated annual
  consumption of surfactants in
  Europe was 1,696,000 metric tons.
• In the same period the estimated
  total consumption of antibiotics
  from all sources was less than
  1,000 metric tons .
                 Current Practices
• Low Level disinfectant cleaners like quats are used for
  damp dusting environmental surfaces with a simple wipe
  and go technique.
• More potent disinfectant cleaners are used in isolation
  areas, for cases of Noroviruses or C. difficile and simply
  when a higher degree of confidence is required.
• Because it is not common practice to maintain an
  appropriate wet contact time, cleaning staff are using
  antimicrobial products as cleaners, not disinfectants.
   – Legally concerns claiming when claiming to disinfect but not
     following manufacturers instructions for use?
    Separate Cleaning From
         Disinfecting.



• One Step Cleaning and
  Disinfecting is contradictory to
  the science of disinfection.
        Focus on Cleaning.
• Use best cleaning practices.
• Prevent spreading contaminants.
    If your institution insist on cleaning with low level
       disinfectant cleaners consider using sodium
   hypochlorite to replace existing cleaning solutions.


• Mild odor in low concentrations.

• Oxidizes organic soils that harbor many problematic
  pathogens.

• Safe in low concentrations.

• Easily formulated into effective cleaning solutions
  without detergent surfactants.

• Reduced environmental pressure on microbial
  populations..
     If your institution insist on cleaning with low level
disinfectant cleaners consider using sodium hypochlorite
           to replace existing cleaning solutions.


 • Packaged in closed looped
   containers with accurate dispensers.
 • Dilute solutions can be made stable
   for months after dilution when
   stored in clean work place bottles.
 • Use in conjunction with best
   cleaning practices .
• All 9 rooms of patients with CDI
positive cultures prior to cleaning vs. 7
(78%) after housekeeping cleaning (p =
0.5), vs. only 1 (11%) after bleach
disinfection by research staff (p = 0.031)

• After an educational intervention,
rates of environmental contamination
after housekeeping cleaning were
significantly reduced
Moore & Griffith. J Hosp Infect 2006;64:379-85.
• All 9 rooms of patients with CDI
positive cultures prior to cleaning vs. 7
(78%) after housekeeping cleaning (p =
0.5), vs. only 1 (11%) after bleach
disinfection by research staff (p = 0.031)

• After an educational intervention,
rates of environmental contamination
after housekeeping cleaning were
significantly reduced
       Targeted disinfection after
               cleaning.
• Limit disinfectant use to disinfection.
• Replace residue depositing disinfectants.
• Use one disinfectant considered effective on all
  hospital pathogens.
• Use cleaning products compatable with hospital
  disinfectant.
• Use safe storage, handling and in use practices.
• Sodium hypochlorite is very effective in short contact
  times when applied to pre cleaned surfaces.
Michael Rochon
Cogent Environmental Solutions
michael@ecogent.ca
1-877-994-9908

				
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