| A surgical mask is intended to be worn
by health professionals during surgery and at other times to catch the
bacteria shed in liquid droplets and aerosols from the wearer's mouth and
nose.
Outside health care facilities, simple,
inexpensive masks of similar appearance are commonly worn in heavily populated
centres in East Asia to help prevent spreading the common cold.
Furthermore they were widely used in
China, Hong Kong, Vietnam, and Toronto, Canada during outbreaks of the
SARS virus, during the 2007 avian bird flu pandemic in Japan and more recently
in Mexico City during the swine flu outbreak.
Modern surgical masks are made from
paper or other non-woven material, and are discarded after each use.
Simple surgical masks protect wearers
from splashes in the mouth with body fluids. They also remind wearers not
to touch their mouth or nose, which could otherwise transfer viruses and
bacteria after having touched a contaminated surface (fomite). They can
also reduce the spread of infectious droplets (carrying bacteria or viruses)
that are created when the wearer coughs or sneezes. They are not designed
to protect the wearer from inhaling such particles. A surgical mask will
trap some particles but is much less effective than a mask designed for
this purpose.
A respirator mask conforming to United
States standard NIOSH N95 or European standard EN 149 FFP2 is recommended
to reduce the exposure of the wearer to potentially infectious aerosols
and airborne liquid droplets during contact with pandemic flu patients. |
