ATLANTA - Just over 131 million Americans are now fully vaccinated.
If you are in that group, CDC Director Rochelle Walensky says, you are protected against the virus and do not need to do anything for now.
"You don't need a booster now," Dr. Walensky says. "The discussion about boosters is what happens if that immunity wanes over time, the way it does for influenza vaccines every season, and what we want to make sure of, is, if that were to be the case, we're not caught off guard."
Executives from both Pfizer-BioNTech and Moderna, along with some US health officials say it is likely Americans will need a third dose of the vaccine, probably within about 8 to 12 months of their final dose.
That is because there are questions about how long the protective antibodies triggered by the vaccine will provide a high level of immunity to the virus.
"So, it is possible that, in months to years, we may need a booster to bolster our immunity and make sure we continue to be protected," Dr. Walensky says. "And, we're doing the hard work now to determine when and if that should be the case."
Another question: is how newer, more contagious variants of SARS-CoV-2, the virus that causes COVID-19, could impact how well the vaccines work.
Both Moderna and Pfizer are developing booster shots, including a third dose of their original vaccines and boosters that target specific variants, like the South African or Brazilian variant.
Dr. Walensky says the CDC expects to have more data soon on the question of whether boosters will be needed.
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