Transcript Document

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 coselect 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 communityacquired 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 communityacquired 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 drugresistance 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 peroxidasebased 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
[email protected]
1-877-994-9908