Costco is returning to special shopping hours for seniors and other vulnerable groups, due to a surge in COVID-19 positive case numbers.

At most clubs, 9 a.m. to 10 a.m. Monday through Friday will be reserved for people 60 and older, members with disabilities or a compromised immune system.

Costco was one of the first retailers to require masks in its stores, and last month, the retailer updated its policy to no longer make exemptions for mask-less shoppers citing medical conditions.

With the updated policy, children under two continue to be exempt from wearing a face covering.