Hand hygiene.pdf

tions of short-chain aliphatic alcohols such as ethanol, iso-propanol and n-propanol 1 . With
their strong antibacterial efficacy, the importance of a sustained effect is questionable, as
regrowth of the skin flora takes several hours even without the explicitly sustained effect of
the alcohols.
With regard to the statistical analysis of prEN 12791, the currently suggested model of a
comparative trial is no longer up to date. It should be exchanged for an equivalence trial.
The latest CDC/HICPAC guideline for hand hygiene in health-care settings 7 considers it as
a shortcoming that in vivo laboratory test models use volunteers as surrogates for HCWs,
as their hand flora may not reflect the microbial flora on the hands of caregivers working in
health-care settings. This argument is only valid for testing surgical scrubs, however, because
for evaluating hygienic handwash or rub preparations, protocols include artificial hand contamination.
Furthermore, the antimicrobial spectrum of a product should be known from
the results of preceding in vitro tests.
8.3 NEW METHODS FOR THE FUTURE
Further studies will be needed to identify necessary amendments to the existing test methods
and to evaluate amended protocols, to devise standardized protocols for obtaining more
realistic views of microbial colonization, and to better estimate the risk of bacterial transfer
and cross-transmission 28 .
To summarize, the following amendments to traditional test methods are needed:
• The few existing protocols should be adapted so that they lead to comparable
conclusions about the efficacy of hand hygiene products.
• Protocols should be updated so that they can be performed with economically
justifiable expenditure.
• To be plausible, results of in vivo test models should show that they are realistic
under practical conditions such as the duration of application, the choice of test
organism, or the use of volunteers.
• Requirements for efficacy should not be formulated with a view to the efficacy
of products available on the market, but in consideration of objectively identified
needs.
• In vivo studies in the laboratory should be organized like clinical studies, i.e. as
equivalence rather than as comparative studies.
• Protocols for controlled field trials should help to ensure that hand hygiene products
are evaluated under more plausible, if not more realistic, conditions.
There is no doubt that results from well-controlled clinical studies are urgently needed to
generate epidemiological data on the influence of various groups of hand hygiene products
on the frequency of hand-transmitted hospital infections and antimicrobial-resistant pathogen
cross-transmission, i.e. proof of clinical effectiveness.