Can a Mask Protect You from SARS?
Separating Fact from Fiction about Surgical Masks and SARS
Wearing a mask may protect people from inhaling these droplets and becoming infected, but the masks usually don't fit snugly and can allow droplets to enter the mouth or nose from the edges of the mask.
Although droplet transmission through close, personal contact with an infected individual is believed to be the primary mode of transmission of SARS, health officials have not ruled out the possibility that tiny particles of the SARS coronavirus may also spread the disease through the air. If such transmission is possible, some of these tiny virus particles may pass through a simple surgical mask or enter through an air gap.
Surgical masks also provide no protection for the eyes, and some types of virus particles can enter the body through the eyes as well as the mouth and nose.
In addition, some types of coronaviruses are known to survive on objects for several hours, which means it's possible that person with SARS person could sneeze and infect an object like a door knob that is later touched by someone who then rubs their eyes, nose, or mouth and becomes infected in that manner.
For protecting people from SARS infection, the CDC recommends that healthcare providers who care for SARS patients wear a much more efficient mask known as an N95 respirator. This type of mask is certified by the National Institute of Occupational Safety and Health (NIOSH) as being effective at filtering out at least 95% of airborne particles of a particular size.
There are also N99 and N100 masks that are even more efficient, but N95 masks are considered the standard for preventing infection from most known viruses.
But for these masks to work, they must be properly fitted to make sure there are no gaps between the mask and the skin. The mask is made of a thicker material than regular surgical masks and, when properly fitted, does not allow air to flow outside the mask.
Gerberding says N95 masks are only recommended for healthcare workers caring for SARS patients because they are at greatest risk of becoming infected. In fact, the majority of initial SARS cases were among doctors, nurses, and medical students who cared for the first round of SARS patients and did not wear such protection. Since infection control measures such as wearing N95 masks were implemented, the rate of SARS spread to healthcare workers has been drastically reduced.