Health workers caring for patients who have or may have swine flu should wear a special type of mask called an N95 respirator, not looser-fitting surgical masks, the Institute of Medicine advised Thursday.
Health authorities have stressed that the general public doesn't need to wander around wearing masks against flu, which doesn't spread only through the air. But doctors, nurses and other health workers will come into close, possibly prolonged, contact with the very sick. That puts them at higher risk of catching swine flu than, say, an office worker or restaurant waiter.
Still, "it would be a mistake for anyone to rely on respirators alone as some sort of magic shield," said Kenneth Shine of the University of Texas Health System, Austin, who chaired the Institute of Medicine committee.
Health workers also need to get vaccinated as soon as vaccine is available and take other standard infection-control precautions, including hand-washing, the report said.
Flu spreads both by air — through flying droplets when people cough or sneeze — and by touch. Say someone forgets the sneeze-into-your-elbow advice and uses a hand instead, then touches a doorknob. If you touch that knob next and then put germy hands on your nose or mouth, you've been exposed.
N95 respirators are standard in hospitals for use when treating patients with certain infections, but they're more expensive and not in as plentiful supply as surgical masks.
Officials at the federal Centers for Disease Control and Prevention told reporters today that they're reviewing the IOM report. Dr. Tom Frieden, the agency's director, said that the IOM was charged with looking at health concerns, not cost or supply impact.
He refused to respond to questions about a potential shortage of N95 respirators, saying that CDC needed to review the recommendation more thoroughly.
They also must be properly fitted to form a seal with the user's face, a challenge for men with beards.
But the Institute of Medicine said if properly fitted and used correctly, N95 respirators filter out at least 95 percent of very small airborne particles, smaller than influenza viruses. Simple surgical masks are looser fitting and don't filter out droplets as small.
The Institute of Medicine is part of the National Academies, an independent organization chartered by Congress to advise the government on scientific matters.