ATLANTA, Ga. (CW69 News at 10/CNN) — Retailers around Georgia are re-evaluating their mask policies after the U.S. Centers for Disease Control and Prevention (CDC) updated guidance Tuesday to recommend that fully vaccinated people wear masks indoors in areas with high transmission of COVID-19, which includes nearly two-thirds of all U.S. counties.

The CDC’s new guidance was in response to the rising spread of the new, highly transmissible Delta variant and low vaccination rates.

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Mask rules for customers have been a contentious issue throughout the pandemic and workers in stores and restaurants have often been thrust into the role of carrying out their employers’ mask rules, sometimes with violent consequences. Last month, a customer killed a clerk at Big Bear Supermarket in Decatur in a dispute over face masks.

A Walmart spokesperson said Wednesday that the company has followed CDC guidance throughout the pandemic. “This one is a little more complicated due to county-by-county discretion but expect to hear more from us soon.”

Soon turned out to be Friday when Walmart announced that employees are required to wear masks inside again, regardless of vaccination status, in places with “substantial or high transmission.” The new policy is effective immediately.  Atlanta is considered by the CDC to be in the at risk zone.

Maria Brous, a spokesperson for Publix, said the company was “reviewing the updated CDC guidance” and would provide updates regarding our policies as appropriate.”

Walmart, Publix and most large retailers had removed face covering requirements for vaccinated shoppers in their stores in May, following CDC guidance at the time easing mask-wearing for people vaccinated against COVID-19.

Groups representing companies and workers immediately came out on opposite sides on the latest CDC update, underscoring a divide in the industry over mask rules and how to implement them.

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The National Retail Federation, a trade association for retailers, said in a statement Tuesday that “it is truly unfortunate that mask recommendations have returned when the surest known way to reduce the threat of the virus is widespread vaccination.”

But Marc Perrone, president of the United Food and Commercial Workers, a union representing 1.3 million food and retail workers, said in a statement that the guidance was “a critical step that sounds the alarm about the explosion in [COVID-19] cases and makes clear that wearing masks indoors is critical to stopping the spread of this deadly virus.”

Perrone added that the CDC recommendation “does not go far enough” and called for a national mask mandate to slow the spread of the virus.

The CDC emphasized Tuesday that COVID-19 vaccinations are effective at preventing severe illness, hospitalization, and death. The CDC also noted that the highest spread of COVID-19 cases and severe outcomes is happening in areas with low vaccination rates and among unvaccinated people.

Currently, only 49.2% of the U.S. population is fully vaccinated against COVID-19, according to the CDC.

Major retailers have not required their store workers to get vaccinated. Instead, they are offering paid time off, free transportation to vaccination sites and incentives like bonuses to encourage workers to get vaccinated, Mary McGinty, a spokesperson for the National Retail Federation, said in an email.

Mark Cohen, director of retail studies at Columbia Business School and the former chief executive of Sears Canada, said that retailers were hesitant to require workers to get vaccinated out of fear some may quit or that such a requirement would alienate customers.

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