Experts Debate Usefulness of Face Masks

WASHINGTON – How much protection would a face mask offer during a worldwide flu epidemic? And would people need a fresh one every day or even every few hours?

There aren’t clear answers, public health experts said Monday as the Institute of Medicine grappled with what advice to offer the federal government.

Health workers use masks – simple surgical masks or better-filtering ones called N95 respirators – to prevent infection while caring for sick patients. But the public undoubtedly will turn to masks as well if a flu pandemic strikes, and experts say supplies will quickly run short.

Both types of masks are supposed to be used once and discarded. So federal health officials asked the IOM, a prestigious group of independent scientists, to determine if there are ways that health workers could reuse their N95 masks – and if average citizens need reusable masks, too.

The IOM will issue its report this spring.

At a public meeting Monday, health experts cited a host of questions. Among them: how long the masks work once donned; whether reused masks could be contaminated and spread infection; how to ensure they’re worn correctly – N95 masks have to be fitted to the user’s face and are hard to breathe in for long stretches.

And would wearing a mask on, say, the subway protect people enough, or should they have driven or stayed home? Linda Chiarello of the Centers for Disease Control and Prevention said if masks eventually are recommended for the public, the advice must not create a false sense of security.

"The lack of clear data … is a dilemma for those of us on the front lines," said Dr. Jeff Durchin of the Seattle-King County Health Department, adding that people already call health departments to ask what masks they should personally stockpile.

"We should not be talking about the reusability of masks or other devices until we know whether they actually work to begin with," said Jeffrey Levi of Trust for America’s Health, a nonprofit health advocacy group.