The debut of Omicron-specific vaccines raises a thorny question: How long should you wait between shots?
The director of the Centers for Disease Control and Prevention on Thursday recommended that the vast majority of Americans receive an updated coronavirus booster shot, adding a critical new tool to the country’s arsenal as it tries to blunt an expected wintertime surge of the virus.
The decision cleared the way for health workers to begin giving people the redesigned shots within days. And it marked a milestone in the fight against a rapidly shape-shifting pathogen: For the first time in the pandemic, manufacturers have capitalized on the potential of mRNA technology to begin distributing a Covid vaccine that perfectly matches the circulating strain of the virus, a feat that had long seemed improbable.
For all their promise, the arrival of updated boosters also adds another wrinkle to what is the country’s most complicated vaccine. Vaccine recipients have already had to parse shifting eligibility rules and decide between brands. Now they face a weighty new question: how long to wait after their last vaccine dose or infection before seeking an updated booster.
In authorizing the new boosters, federal regulators said on Wednesday that people needed to wait at least two months since their last Covid vaccine dose to receive an updated booster shot. Several members of a panel of expert advisers to the C.D.C. expressed concern during a meeting on Thursday that two months was too short, but the C.D.C. pushed to endorse the same minimum interval.