Hand hygiene.pdf

9. REVIEW OF PREPARATIONS USED FOR HAND HYGIENE
9.1 WATER
Routine handwashing is the removal of dirt, organic material and transient microorganisms.
The purpose of handwashing for routine patient care is to remove microbial contamination
acquired by recent contact with infected or colonized patients or with environmental
sources and to remove organic matter from the hands.
Water is a good solvent for a large number of substances and is often called the universal
solvent. It is stable, has a high boiling point and has very high surface tension, an important
characteristic for cleansing soiled hands. Because of its properties, water cannot directly
remove soils such as fats, oils and proteins which are common components of organic soil.
For efficacious cleansing of soiled hands, it is essential that soils dissolve or are suspended
in water to allow them to be flushed away. Soaps and detergents are able to dissolve fats
and oils: they loosen them and disperse them into the water. Soaps also ensure that soils
are kept in suspension so that they can be flushed away with the water. Thus water alone
is not suitable for cleaning soiled hands; soap or detergent is required to be applied along
with water. This is followed by flushing with water. During handwashing, friction and thorough
rinsing are the most important factors for clean hands. Use of medicated or plain soap
seems to have roughly the same effect in preventing diarrhoeal disease, upper respiratory
tract infection or impetigo among children in the community setting 4,5 . The cleansing effect
is probably the result of the friction while spreading the product over the hands and rinsing
afterwards.
9.1.1 ASSOCIATION OF WATER CONTAMINATION WITH INFECTIONS
Drinking-water may be contaminated by any kind of microorganism: bacteria, viruses,
helminths and pathogenic protozoa. Table I.9.1 lists microorganisms that have been documented
as causing or are suspected of causing outbreaks of waterborne diseases, and indicates
their health significance, their persistence in water supplies, and relative infectivity 162 .
9.1.2 WATER CONTAMINATION AND HEALTH CARE-ASSOCIATED INFECTIONS
Contamination of a healthcare institution water supply can occur, and there is a body of
evidence that links nosocomial infections to hospital water or point-of-use water. Attention
should be paid to guaranteeing that sewage is segregated from the water supply of the
hospital. By a Medline search, investigators identified 43 outbreaks associated with health
care where organisms were waterborne, of which 29 had epidemiological and molecular
evidence linking the outbreak to the hospital water system 163 . Sources of the organisms were
hospital water storage tanks, tap water and showers 164-166 . The cause of poor water quality
is the build-up of biofilm, corrosion of distribution systems and tanks or water stagnation.
Biofilms are microbial growths adhering to surfaces through the slime they secrete; they
can build up on any surface exposed to water and bacteria. Among organisms identified in
hospital water and associated with nosocomial infections were Legionella spp., P. aeruginosa
167,168 , Stenotrophomonas maltophilia 169 , Mycobacterium avium 170 , M. fortuitum 171 , M.
chelonae 172 , Fusarium spp. 173 and Aspergillus fumigatus 174 . One of the routes of transmission
of these organisms from water to patient could be through HCWs’ hands if contaminated
water is used to wash them.