By CBSBoston.com Staff

BOSTON (CBS) — The CDC on Tuesday recommended that even fully vaccinated Americans return to wearing face masks indoors in areas where the spread of the coronavirus and the highly contagious Delta variant is substantial. Those new guidelines “make a lot of sense,” Dr. Paul Sax, the clinical director of the infectious disease clinic at Brigham and Women’s Hospital, tells CBSN Boston.

“The Delta variant has become the dominant variant in the United States and in our state,” Sax said. “It’s much more transmissible and so we need to do everything that we can to prevent infection, especially among those who are unvaccinated.”

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More than 5,000 breakthrough cases in fully vaccinated people have been reported in Massachusetts. Sax said they have mostly been pretty mild thanks to effective vaccines, but they can be severe in people who have weakened immune systems and they are at least “very inconvenient” for those who get sick.

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“It’s really a reminder that the virus doesn’t care that we’re tired of it,” Sax said. “It’s basically circulating around and this variant is very contagious. We just need to be careful a bit longer.”

The CDC also recommended that everyone at K-12 schools wear face masks, regardless of vaccination status.

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“For the younger age school kids, mask-wearing indoors makes sense,” Sax said. “I think that’s something we should at least anticipate until we have a good sense of where this Delta variant is going.”

CBSBoston.com Staff