With infections surging due to the fast-spreading Omicron variant, including among the vaccinated, physicians are now urging people to ditch cloth face masks, which they say may not provide enough protection against the virus. Instead, they recommend pairing cloth masks with surgical models or moving on to stronger respirator masks.

The Mayo Clinic began on Thursday requiring all patients and visitors to wear surgical masks or N95 or KN95 masks. Anyone wearing a single-layer, homemade cloth mask, gaiter or bandanna, or a mask with a vent, will be provided a medical-grade mask to wear over it.

Single-layer cloth masks, which many people prefer for comfort and style, can block larger droplets carrying the virus, but aren’t as effective in blocking smaller aerosols or particles carrying the virus, according to infectious-disease specialists.