Healthcare Hygiene magazine August 2020 | Page 35
Barring no-touch technologies, chemical decontamination of
high-touch environmental surfaces invariably incorporates wiping,
but current and widely accepted methods to assess environmental
surface disinfectants do not incorporate that physical action (Sattar
2010) so critical for dislodging and removing dried contamination
to allow better access to and action by the disinfectant. In
view of this, test data from ‘static’ (without any wiping action)
test protocols, and label claims based on them, only show the
microbiocidal potential of a given formulation without indicating
its ability to perform under actual field use. There is, therefore, a
need to generate test data on such formulations via a ‘dynamic’
(combining physical action of wiping with chemical disinfection
process) test protocol reflecting field use of the process. Such
information would better inform disinfectant manufacturers,
government regulators as well as infection preventionists.
It is with this example in mind that EvSOP© tested most commercially
available wipes and mops for evidence-based outcomes
to be shared in the future series on science-based cleaning. In her
research paper, How do we assess hospital cleaning? A proposal for
microbiological standards for surface hygiene in hospitals (Journal
of Hospital Infection (2004) 56, 10–15), Dancer stated, “Cleaning
in general has two main functions: first: non-microbiological,
to improve or restore appearance, and prevent deterioration.
Second, microbiological, to reduce the numbers of microbes
present, together with any substances that support their growth
or interfere with disinfection.”
You can clean without disinfecting, but you cannot
disinfect without cleaning”
— Dr. Earle Spaulding
Cleaning
• The removal of material like dust,
soil, blood, and bodily fluid.
• Physically removes rather than
kills microorganisms. Accomplished
with water, detergents, and
mechanical action.
• Is always essential prior to
disinfection or sterilization.
• A surface that has not been
cleaned effectively cannot be
properly disinfected or sterilized.
Disinfecting
• The inactivation of pathogens.
• Usually involves chemicals, heat, or
ultraviolet light.
• Sterilization destroys microbial life
including bacteria, viruses, spores,
and fungi and is not performed by
surgical cleaning or environmental
services staff.
• The most common disinfectants
used are quaternary ammonium
compond products, hydrogen
peroxide-based products, and sodium
hypochlorite (bleach).
These are the two basic functions we need to look at
for EPA-registered, hospital-grade disinfectants to have full
efficacy, and to remove potential sources of infection. Notice
the importance of the physical removal in the CDC Guidelines
for Environmental Infection Control in Health-Care Facilities,
section 2b:
Disinfectant/detergent formulations registered by EPA are
used for environmental surface cleaning, but the actual physical
removal of microorganisms and soil by wiping or scrubbing is
probably as important, if not more so, than any antimicrobial
effect of the cleaning agent used.
So, evaluation of a cleaning tool -- albeit wiper or mop -- must
include how it performs in both the cleaning and disinfection
process. It must trap, capture, and remove bacteria, virions,
spores, dirt, dust, soil, blood, and body fluid, while absorbing
and eluting the disinfectant to achieve the desired wet contact
time per the manufacturer’s label.
At the outset of the EvSOP© series, readers were introduced
to a set of criteria upon which each product should be tested.
Due to the COVID-19 pandemic, most people know the importance
of cleaning and disinfecting the environment to ensure a
hygienic environment. What appears to be clean and assumed
to be hygienic can contaminate the environment and cause a
healthcare acquired infection.
With the conventional methods, the method of
reporting a result from a test is by colony forming
units (CFU) per unit of testing (typically CFU per
mL or per 100mL). A CFU does not necessarily
equate with a number of microorganisms present
in the sample but it does provide an indicator of
the bioburden load. This is because a CFU is an
View Evaluation
Criteria
estimate of one or more microbial cells which, on the introduction
of microbial growth media, can form macro-colonies under the
conditions of the test. One colony forming unit is expressed as 1
CFU. In relation to pharmaceutical processing, bioburden testing
is implemented in order to assess the quality of the starting
materials and to track process hygiene as the product is being
manufactured.
Healthcare-Grade Ultra Microfiber (H-GUM) used in healthcare
facilities is not expected to be sterile, only hygienic. Bioburden
assessment is not a requirement of the final product. To expect
non-sterile products used in a non-sterile environment to produce
a sterile environment or surface is non-sensical, unrealistic,
and beyond the realm of the necessary. It should be expected
that infection prevention textiles used by EVS in a non-sterile
environment may contain a level of bioburden, and bioburden is
not another name for pathogens. H-GUM is effective at providing
a log-10 5 reduction of surface bacteria in and of itself and, with
the proper disinfectant and use, a log-10 7 is attainable. When
laundered according to CDC guidelines, H-GUM releases bacteria,
spores, and other biomaterial sufficiently to render the product
hygienic and effective at removing bioburden from surfaces
sufficient to rendering them hygienic.
What to remember from all of this? Quite simply, EVS teams
must be equipped with knowledge, proper cleaning tools including
H-GUM, EPA-registered and hospital-grade disinfectants, and
sufficient time to incorporate them. When all four of these
essential factors are in place, the microbial jungle is not so
frightening; that is, at least until someone with unwashed hands
touches a surface.
Paul J. Pearce, PhD, has more than 40 years of medical and
environmental laboratory testing and teaching experience. Pearce’s
training and work in microbiology, chemistry, human physiology
and medicine have enabled him to help thousands of people as
they strive to improve their lives.
John Scherberger, FAHE, is the owner of Healthcare Risk
Mitigation in Spartanburg, S.C. He is a subject matter expert in
healthcare environmental services, healthcare linen and laundry
operations, and infection prevention.
www.healthcarehygienemagazine.com • august 2020
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