On July 27, 2021, the Centers for Disease Control and Prevention (CDC) updated its COVID-19 guidance. The revised guidance, which has significant implications in the employment context, recommends that fully-vaccinated individuals wear masks in “public indoor settings in areas of substantial or high transmission.” The guidance further recommends that vaccinated persons be tested after a known or suspected COVID-19 exposure. The CDC’s guidance reverses its May 2021 guidance, which advised that fully-vaccinated individuals could generally stop wearing masks and cease social distancing. The CDC’s new guidance comes amidst a recent uptick in COVID-19 cases stemming from the highly-infectious Delta variant and is already complicating employers’ COVID-19 policies and return to work plans.

Updated masking recommendation

The CDC’s revised guidance acknowledges that fully vaccinated individuals can become infected with COVID-19 despite being vaccinated in a “breakthrough” infection. The CDC further acknowledges that, while breakthrough infections “happen in only a small proportion of the people who are fully vaccinated,” individuals with breakthrough infections can spread COVID-19. As a result of these concerns, while not referencing the workplace specifically, the CDC now recommends that all individuals, regardless of vaccination status, wear masks in public indoor settings in areas of substantial or high transmission.

Updated testing recommendation

The CDC also revised its testing recommendations. For fully vaccinated individuals experiencing COVID-19 symptoms, or who are aware of an actual or potential exposure to the virus, the CDC now recommends getting tested three to five days after suspected or known exposure and wearing a mask in public indoor settings for 14 days, or until receiving a negative test result, whichever is sooner.

Area of substantial or high transmission

To determine whether an employer operates in an area of “substantial or high transmission,” businesses can consult the CDC’s COVID Data Tracker that shows the rate of community transmission by county. The CDC regularly updates the Data Tracker and employers should consult the Data Tracker for the latest status reports to properly evaluate COVID-19 policies and return to work plans.

Public indoor setting

Employers may be wondering whether an office setting constitutes a “public indoor setting” under the CDC’s revised guidance. Unfortunately, the CDC’s revised guidance does not address that issue. As a result of the uncertainty, most employers are taking a conservative approach and proactively revising their masking policies to require masks for all employees, regardless of vaccination status.

Local guidelines and mandates

Employers should remember that the CDC’s July 27, 2021 guidance is only one facet of the COVID-19 legal analysis. Certain state and local governments (e.g., Los Angeles County, California; Clark County, Nevada; Savannah, Georgia; Kansas City, Missouri) have implemented, or are considering implementing, stricter requirements for masking and other COVID-19 protections as infection rates continue to climb. Employers should continue to monitor state and local regulations regarding COVID-19 to ensure compliance with all applicable legal obligations


The CDC’s updated guidance highlights the changing landscape employers must navigate during the ongoing COVID-19 pandemic. Reed Smith’s labor and employment attorneys are available to assist and advise on COVID-19 employment policies and procedures.