(Bloomberg) -- Faced with a surge in coronavirus cases driven by the fast-spreading omicron variant, U.S. health officials urged wider use of medical-grade face masks in the general public. 

The U.S. Centers for Disease Control and Prevention revised earlier guidelines that had discouraged the use of gold-standard N95 masks in new guidance published Friday. The agency had earlier suggested reserving such masks for medical personnel. 

Health officials are looking for ways to limit the spread of omicron, which preferentially targets the upper airways and has spread at least twice as quickly as delta. The agency recently relaxed Covid-19 guidelines to say that people can leave isolation five days after their symptoms stop if they wear masks in public for an additional five days. 

The agency continues to recommend that people age 2 and older, regardless of vaccination status, wear well-fitting masks while indoors in public spaces, and stresses that any mask is better than no mask. 

Read More: Should I Be Wearing an N95 or KN95? Understanding the Evolving Advice on Masks

CDC also issued new standards that will grade masks as being “workplace performance” and “workplace performance plus.” The standards are based on masks’ filtration, breathability and leakage ratio, and masks will be labeled for authenticity, the agency said.

Speculation about the update earlier this week contributed to a surge in prices for N95, considered the gold standard, and KN95 face coverings on sites like Amazon.com. Worried consumers abandoned their simple cloth or surgical masks in search for something more protective.

Meanwhile, Covid-19 cases are continuing to climb across the country, threatening to upend the lives of workers and students who are infected or exposed to the virus. Health officials have been encouraging all adults to get booster doses.

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