It is expected that the U.S. will surpass 100 million people who have received at least one dose of vaccine Friday. More than 56 million Americans are fully vaccinated, according to the CDC.
A person is considered fully vaccinated two weeks after their last dose of Covid-19 vaccine. That gives the body enough time to build antibodies against the virus.
This latest guidance offers another step toward resuming normal activity for those who have received both doses of the Pfizer-BioNTech or Moderna shots or one shot of the single-dose vaccine from Johnson & Johnson.
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The CDC said Covid-19 tests are no longer required for fully vaccinated people before or after a trip within the U.S., and there is no need for them to self-quarantine. The guidance doesn’t mention whether people need proof of vaccination to travel, though no U.S. airlines currently require such documentation.
The same rules apply to vaccinated people traveling internationally, with some exceptions. Some destination countries may require a negative Covid-19 test for entry. And the CDC recommends people test negative before coming back to the U.S.
And mitigation measures remain even for vaccinated travelers: wear masks, avoid large crowds and wash hands frequently.
Indeed, all U.S. airlines still require passengers to wear masks.
"Taking prevention measures to stop the spread of Covid-19 is the path out of this pandemic," Walensky said.
The CDC has been slowly offering guidance on what people can do once fully vaccinated. In early March, the agency said they may safely gather with small groups from other households without wearing masks or physically distancing, even if those people have not yet had their shots.