WHO Guidelines on Hand Hygiene in Health Care - Safe Care ...

PART I. REVIEW OF SCIENTIFIC DATA RELATED TO HAND HYGIENE
Table I.10.1
Basic experimental design of current methods to test the efficacy of hand hygiene and surgical hand preparation formulations
Method Test organism(s) Basic procedure
EN 1499
(hygienic handwash)
EN 1500
(hygienic handrub)
ASTM E-1174
(efficacy of HCW or
consumer handwash
formulation)
ASTM E-1838
(fingerpad method
for viruses)
ASTM E-2276
(fingerpad method
for bacteria)
ASTM E-2613
(fingerpad method
for fungi)
ASTM E-2011
(whole hand method
for viruses)
EN 12791
(surgical hand
preparation)
ASTM E-1115
(test method for
evaluation of
surgical handscrub
formulations)
E. coli
(K12)
E. coli
(K12)
S. marcescens
and E. coli
Adenovirus,
rotavirus, rhinovirus
and hepatitis A virus
E. coli,
S. marcescens,
S. aureus, and
S. epidermidis
Candida albicans
and Aspergillus
niger
Rotavirus and
rhinovirus
Resident skin
flora (no artificial
contamination)
Resident skin
flora (no artificial
contamination)
Hands washed with a soft soap, dried, immersed in broth culture for 5 seconds, excess
fluid drained off, and air-dried for 3 minutes. Bacteria recovered for the initial values by
kneading the fingertips of each hand separately for 60 seconds in 10 ml of broth without
neutralizers. Hands removed from the broth and treated with the product following the
manufacturer’s instructions (but for no longer than 1 minute) or the reference solution (a
20% solution of soft soap). Recovery of bacteria for final values (see EN 1500).
Basic procedure for hand contamination and initial recovery of test bacteria same as
in EN 1499. Hands rubbed for 30 seconds with 3 ml of isopropanol 60% v/v; same
operation repeated with a total application time not exceeding 60 seconds. The
fingertips of both hands rinsed in water for 5 seconds and excess water drained off.
Fingertips of each hand kneaded separately in 10 ml of broth with added neutralizers.
These broths are used to obtain the final (post-treatment) values. Log10 dilutions of
recovery medium containing neutralizer are prepared and plated out. Within 3 hours, the
same subjects tested with the reference formulation or the test product. Colony counts
obtained and log reductions calculated.
To test the efficacy of handwash or handrub agents on the reduction of transient
microbial flora. Before baseline bacterial sampling and prior to each wash with the test
material, 5 ml of a suspension of test organism are applied to and rubbed over hands.
Test material put onto hands and spread over hands and lower third of forearms with
lathering. Hands and forearms rinsed with water. Elutions are performed after required
number of washes using 75 ml of eluent for each hand in glove. The eluates are tested
for viable bacteria.
10 μl of the test virus suspension in soil load placed at the centre of each thumb- and
fingerpad, the inoculum dried and exposed for 10–30 seconds to 1 ml of test formulation
or control. The fingerpads then eluted and eluates assayed for viable virus. Controls
included to assess input titre, loss on drying of inoculum, and mechanical removal of
virus. The method applicable to testing both handwash and handrub agents.
Similar to ASTM E-1838.
Similar to ASTM E-1838.
This method is designed to confirm the findings of the fingerpad method (E-1838), if
necessary. Both hands are contaminated with the test virus, and test formulation is used
to wash or rub on them. The entire surface of both hands eluted and the eluates assayed
for infectious virus.
Same as for EN 1500 with the following exceptions: no artificial contamination; reference
hand antisepsis 3-minute rub with n-propanol 60% v/v; longest allowed treatment
with product 5 minutes; 1 week between tests with reference and product. Test for
persistence (3 hours) with split hands model is optional (product shall be significantly
superior to reference).
The method is designed to assess immediate or persistent activity against the resident
flora. Subjects perform simulated surgical scrub and hands sampled by kneading them
in loose-fitting gloves with an eluent. The eluates are assayed for viable bacteria.
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