The science behind the CDC's new mask recommendations

PHILADELPHIA (WPVI) -- Health officials had been asking people to keep their masks on because there were some elements of the vaccine that they just didn't know yet.

But now the director of the CDC says the science is in, and it's good.

"Once you are fully vaccinated, two weeks after your last dose, you can shed your mask," Dr. Rochelle Walensky said.

It's the words so many Americans have been longing to hear and it comes as the number of cases has dropped 45% since everyone 16 and older became eligible for the Covid-19 vaccine.

The U.S. is also approaching 60% of adults with at least their first dose.

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In a striking move to send the country back toward pre-pandemic life, the CDC will ease indoor mask-wearing guidance for fully vaccinated people.

Walensky points to new research behind their new recommendation, with several studies showing three things:

1.) The vaccines are highly effective at preventing infection, proven in a clinical trial and now in the real world

2.) The vaccines are effective against variants spreading in the U.S.

3.) The vaccines are effective at preventing transmission of the virus

And more evidence of the impact of the vaccine is coming from the Cleveland Clinic. From January to April, 4,300 people were admitted to the hospital there with Covid-19. Ninety-nine percent of those patients were not fully vaccinated.

"It cannot be more clear the message that vaccines work and it's the key action that we need to do to get back to our normal lives as they were before coronavirus," Dr. Eduardo Mireles said.

There are caveats: the CDC is still asking masks to be worn on public transportation and in healthcare settings.

Also, anyone with a compromised immune system should talk to their doctor to find out what is best.
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