From http://www.promedmail.org
Date: Thu 13 Jun 2002
From: Paul Webber
An Alternative to Chlorine-based Biocides
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The request for information from Dr. Wheeler [see: " Norwalk-like
virus, decontamination: RFI 20020612.4475"] was forwarded to me for
my opinion. The moderator requested a possible alternative to
chlorine-based biocides to battle Norwalk virus and Norwalk-like
viruses (NLV). Undoubtedly, chlorine bleach (NaHCl) at 5000 - 10 000
ppm will have a cidal affect on the pathogen but is, as is noted,
very harmful to surfaces, equipment and users. Perhaps the concern
for worker safety would even eclipse the sanitizing effects.
A Canadian-made and widely accepted possible alternative is
Accelerated Hydrogen Peroxide (AHP). Several disinfectant products,
including a high-level disinfectant, have been created with this
remarkable (my opinion) technology. Developed and manufactured by
Virox Technologies Inc () of
Toronto, AHP has documented cidal affects against non-enveloped
viruses. AHP disinfectants were tested against Poliovirus type 1
(Sabin) with standard organic and hard water challenges, and were
found to reduce the pathogen by almost 99.999 percent with a 5-minute
contact time. Documented evidence against poliovirus allows
manufacturers to claim efficacy against all non-enveloped viruses,
including Norwalk virus and NLV.
Further, the manufactures have shown that the in-use dilution of the
disinfectant that employs AHP technology is safe on all
colour-stabilized fabrics (including carpet, drapery, air filters,
etc.) and most metals. Some soft metals, when left to soak for a
longer period of time, exhibit corrosion. The product is marketed as
safe for contact with skin, eyes, respiratory and digestive systems,
and has no noticeable odour or colour additives.
I put forward that this may be an acceptable alternative to
chlorine-based biocides. To my knowledge is it as yet unavailable in
the United States, but widely distributed and used in Canada and
other nations.
Date: Mon 17 Jun 2002
From: Marc-Alain Widdowson
Another Thought on Norwalk-like Virus Decontamination
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There is a real gap in knowledge of which disinfectants (apart from very
high concentrations of sodium hypochlorite (bleach) solution) can be used to
decontaminate the environment in protracted "person-to-person" outbreaks of
Norwalk-like viruses so often a problem in cruise ships.
A recent paper (2001) in the Journal of Food Protection (Gulati et al: 4
(9) 1430-4) uses feline calicivirus as a model for Norwalk-like viruses.
The evidence presented suggests that phenolic compounds at concentrations
of twice the manufacturer's recommendations (which are 1:256 dilution of
4.25 percent o-benzyl p-chlorophenol and 4.75% o-phenylphenol) might be the
most effective disinfectant against Norwalk-like viruses. This compares
with sodium hypochlorite, which even at concentrations of 800 ppm was not
particularly effective.
I don't, however, know the effects of phenolics on soft furnishings.