face masks

The Centers for Disease Control and Prevention hasn't budged on its guidance that vaccinated people can skip mask-wearing, but some local governments faced with surging cases are going back to mandates, such as Los Angeles County, which recently mandated indoor mask use, including at places like bars and restaurants. Patrick T. Fallon/AFP via Getty Images hide caption

For about a year, major U.S. commercial airlines have required all passengers who are older than 2 to wear face masks on flights. Joe Raedle/Getty Images hide caption

A CVS pharmacist gives the Pfizer/BioNTech COVID-19 vaccine to a resident at the Emerald Court senior living community in Anaheim, Calif., in January. Federal health officials have revised advice on nursing home visitations for the first time since September. Paul Bersebach/MediaNews Group via Getty Images hide caption

Agnes Boisvert, an ICU nurse at St. Luke's hospital in downtown Boise, Idaho, spends every day trying to navigate between two worlds. One is a swirl of beeping monitors, masked emotion and death; the other, she says, seems oblivious to the horrors occurring every hour of every day. Isabel Seliger for NPR hide caption

As new, more transmissible variants of the coronavirus spread, the CDC says wearing a cloth mask over a surgical mask offers increased protection against the virus. Olivier Douliery/AFP via Getty Images hide caption

Tie the ear loops close to the edges of the mask and tuck in the side pleats to minimizes gaps (left). Or use a hair clip to hold the ear loops tightly at the back of the head to achieve a tighter seal. Michele Abercrombie/NPR hide caption

A health worker holds an N95 respirator in the emergency room at OakBend Medical Center in Richmond, Texas, in July. N95s are tested and approved by a federal agency as having demonstrated that they can filter out a minimum of 95% of airborne particles. Mark Felix/AFP via Getty Images hide caption

South Korea's KF94 mask does a good job concealing the Mona Lisa's smile — but how effective is it at preventing coronavirus spread? Here, masked pedestrians stroll through a shopping district in Seoul. Chung Sung-Jun/Getty Images hide caption

Staff and residents of the Ararat Nursing Facility in the Mission Hills neighborhood of Los Angeles got COVID-19 shots on Jan. 7. Coronavirus cases, hospitalizations and deaths have been surging throughout Los Angeles County. Mario Tama/Getty Images hide caption