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

PART I. REVIEW OF SCIENTIFIC DATA RELATED TO HAND HYGIENE
studies have also documented that the hands (or gloves) of
HCWs may be contaminated after touching inanimate objects
in patients’ rooms. 73,111,112,125-130 Furthermore, a recent two-part
study conducted in a non-health-care setting found in the
initial phase that patients with natural rhinovirus infections often
contaminated multiple environmental sites in their rooms. In
the second part of the study, contaminated nasal secretions
from the same individuals were used to contaminate surfaces
in rooms, and touching contaminated sites 1–178 hours later
frequently resulted in the transfer of the virus to the fingertips of
the individuals. 131
Bhalla and colleagues studied patients with skin colonization
by S. aureus (including MRSA) and found that the organism
was frequently transferred to the hands of HCWs who touched
both the skin of patients and surrounding environmental
surfaces. 96 Hayden and colleagues found that HCWs seldom
enter patient rooms without touching the environment, and
that 52% of HCWs whose hands were free of VRE upon
entering rooms contaminated their hands or gloves with
VRE after touching the environment without touching the
patient. 114 Laboratory-based studies have shown that touching
contaminated surfaces can transfer S. aureus or Gram-negative
bacilli to the fingers. 132 Unfortunately, none of the studies dealing
with HCW hand contamination was designed to determine if
the contamination resulted in the transmission of pathogens to
susceptible patients.
Many other studies have reported contamination of HCWs’
hands with potential pathogens, but did not relate their findings
to the specific type of preceding patient contact. 78,79,94,132-142 For
example, in studies conducted before glove use was common
among HCWs, Ayliffe and colleagues 137 found that 15% of
nurses working in an isolation unit carried a median of 1x 10 4
CFU of S. aureus on their hands; 29% of nurses working in a
general hospital had S. aureus on their hands (median count,
3.8 x 10 3 CFU), while 78% of those working in a hospital for
dermatology patients had the organism on their hands (median
count, 14.3 x 10 6 CFU). The same survey revealed that 17–30%
of nurses carried Gram-negative bacilli on their hands (median
counts ranged from 3.4 x 10 3 CFU to 38 x 10 3 CFU). Daschner 135
found that S. aureus could be recovered from the hands of
21% of ICU caregivers and that 21% of doctors and 5% of
nurse carriers had >10 3 CFU of the organism on their hands.
Maki 80 found lower levels of colonization on the hands of HCWs
working in a neurosurgery unit, with an average of 3 CFU of
S. aureus and 11 CFU of Gram-negative bacilli. Serial cultures
revealed that 100% of HCWs carried Gram-negative bacilli at
least once, and 64% carried S. aureus at least once. A study
conducted in two neonatal ICUs revealed that Gram-negative
bacilli were recovered from the hands of 38% of nurses. 138
7.3 Organism survival on hands
Several studies have shown the ability of microorganisms to
survive on hands for differing times. Musa and colleagues
demonstrated in a laboratory study that Acinetobacter
calcoaceticus survived better than strains of A. lwoffi at 60
minutes after an inoculum of 10 4 CFU/finger. 143 A similar study
by Fryklund and colleagues using epidemic and non-epidemic
strains of Escherichia coli and Klebsiella spp. showed a 50%
killing to be achieved at 6 minutes and 2 minutes, respectively. 144
Noskin and colleagues studied the survival of VRE on hands
and the environment: both Enterococcus faecalis and E.
faecium survived for at least 60 minutes on gloved and ungloved
fingertips. 145 Furthermore, Doring and colleagues showed that
Pseudomonas aeruginosa and Burkholderia cepacia were
transmissible by handshaking for up to 30 minutes when the
organisms were suspended in saline, and up to 180 minutes
when they were suspended in sputum. 146 The study by Islam
and colleagues with Shigella dysenteriae type 1 showed its
capacity to survive on hands for up to 1 hour. 147 HCWs who
have hand dermatitis may remain colonized for prolonged
time periods. For example, the hands of a HCW with psoriatic
dermatitis remained colonized with Serratia marcescens for
more than three months. 148 Ansari and colleagues 149,150 studied
rotavirus, human parainfluenza virus 3, and rhinovirus 14 survival
on hands and potential for cross-transfer. Survival percentages
for rotavirus at 20 minutes and 60 minutes after inoculation
were 16.1% and 1.8%, respectively. Viability at 1 hour for human
parainfluenza virus 3 and rhinovirus 14 was