The CDC said more than 92 million people have taken at COVID-19 vaccine shot, with 18 percent having received at least one shot, while just over 9 percent have received both vaccine doses.

Even with the new guidance, however, the CDC said persons who are fully vaccinated should continue to follow COVID-19 guidelines put in place to mitigate spread. This includes the wearing of masks and social distancing while in public or when visiting unvaccinated people who are at higher risk for severe cases of the deadly disease.

CDC Director Rochelle Walensky said at a press briefing that, “Our guidance must balance the risk to people who have been fully vaccinated, the risks to those who have not yet received the vaccine, and the impact on the larger community transmission of COVID-19." The CDC also kept its guidance that people continue to hold off from long train or plane trips.

COVID-19 cases in the US have been down about 70 percent from a winter surge, while the government's vaccination drive has been ramping up. President Joe R. Biden has said the US will have enough vaccines to inoculate every adult American by the end of May.

President Joe R. Biden has said the US will have enough vaccines to inoculate every adult American by the end of May 2021.

Vaccinated persons can still get COVID-19

The CDC said it is possible for persons who have been vaccinated to become ill with the virus again, though the chances are low. It is also possible for vaccinated people to spread the virus to persons at severe risk for the disease. While the authorised vaccines have proven highly effective at preventing severe cases and death, it remains unclear how effective they are at minimizing spread. Early data, however, suggest that inoculated people are less likely to become ill a second time with the virus, and are less likely to spread it.

Persons are considered fully vaccinated two weeks after taking the second dose of either the Pfizer or Moderna vaccine, or two weeks after one dose of the Johnson & Johnson vaccine.

The CDC said vaccinated people don't need to quarantine or receive a test after being exposed to the virus. And they can visit unvaccinated people without wearing masks or social distancing, so long as those persons are at low risk for severe cases of the disease.

For persons living in non-medical facilities such as prisons, they are to still get tested or quarantine after being exposed to COVID-19, said the CDC. Vaccinated employees at those facilities or other heavily populated workplaces don't need to quarantine, but should continually get tested.

Vaccinated persons are at lower risk of getting reinfected when participating in outdoor activities, going to the gym, or eating indoor at restaurants.

The CDC stressed that the added safety provided through vaccination does not mean that those individuals should stop following safety protocols. And vaccinated persons showing signs of reinfection should isolate themselves and get tested, the CDC said.