Will double-masking better protect you from covid?

When it comes to face masks, are two better than one?

Some health experts — including Dr. Anthony Fauci, the nation’s top infectious-disease expert — have recently suggested wearing two face masks for extra protection during the covid-19 pandemic.

“It just makes common sense that it likely would be more effective,” Fauci said, although later in the week he appeared to backpedal and urged people to follow guidelines from the Centers for Disease Control and Prevention.

The CDC recommends that people wear masks that fit snugly and have “two or more layers of washable, breathable fabric.”

Dr. Amesh Adalja — a Pittsburgh-based infectious disease expert and senior scholar at the Johns Hopkins Center for Health Security — offered insights on whether double masking is a necessary step to stopping the spread of covid-19.

How much more effective is double masking compared to wearing a single mask?

Adalja: It all depends on how effective your singular mask is. If you have a highly effective single mask, there is little benefit to wearing a double mask. The rationale is that a lot of people have flimsy masks. If you have an adequate mask, one that’s consistent with CDC guidance, you’re not going to get much added benefit with double masks. It all depends on the mask.

Is an N95 mask sufficient on its own?

Adalja: An N95 is sufficient in a medical setting. The CDC doesn’t even recommend N95s for the public.

What other masks are effective enough on their own, without double masking?

Adalja: If they have a cloth mask that has multiple layers — three layers or so — in it, that would be sufficient. I take care of covid-19 patients and I don’t double mask.

For those who do opt to wear two masks, what’s the most effective combination of masks?

Adalja: I don’t think we have strong data to be able to make these types of determinations. The goal is to have multiple layers. This double mask thing — it actually starts from an academic paper that has been mildly misinterpreted. It was really about a situation when you have a flimsy mask.

How often should people be washing or replacing their masks?

Adalja: You should wash them regularly if you’re wearing a cloth mask. Maybe have a couple so that you’re rotating them and washing them at least once a week.