Fears about the new omicron variant have delivered a boost to vaccination rates since the Thanksgiving holiday.

“Most people just need a little extra push to go get that vaccine,” said Dr. Keri Althoff, an epidemiologist at the Johns Hopkins Bloomberg School of Public Health. “It just takes a little bit of a change in the environment and what we're seeing in the viral landscape … to see this bump.”

Scientists in South Africa first raised the alarm about the new variant on Nov. 24. Its rapid rise in South Africa — from about 3,400 cases recorded on Nov. 26 to roughly 8,500 cases recorded on Dec. 1 — has worried infectious disease experts there. President Joe Biden quickly imposed travel restrictions on eight African countries days after, predicting that “sooner or later, we're going to see cases” in the United States.

Since then, the number of shots administered each day has maintained a steady uptick from about 642,000 on average the week ending Nov. 27 to nearly 1.8 million on Dec. 7, according to a New York Times analysis of federal data.


To date, roughly 60% of all Americans are fully vaccinated, meaning two weeks have passed since they received either the single-dose Johnson & Johnson shot or the second dose of the Pfizer-BioNTech or Moderna two-shot vaccine. About 72% of all adults have been fully vaccinated, and that figure is even higher for seniors, at roughly 87%.

Despite evidence of immunity waning over time, the Centers for Disease Control and Prevention does not consider boosters necessary in order to provide full protection from COVID-19. Still, people have been eager to get the extra shots since news of omicron began circulating the globe. Roughly 717,000 people on average got a booster in the week leading up to Nov. 25, compared with about 859,000 leading up to Dec. 5, according to the CDC. More than 1 million adults got a booster shot on Dec. 2 alone.

Meanwhile, rates of administering first and second doses are up but remain low compared to the initial rollout in early 2021, when the people who were eager for the shots got them. Omicron probably won’t convince vaccine holdouts to get their first doses, Althoff said.

“The emergence of a new variant may or may not change the minds of the currently unvaccinated, but we will have to continue to reach out and work toward that. Any motivation to boost people, to make these efforts to get an additional dose or even get their first dose is progress for everybody for the population,” she said.


Early evidence suggests the omicron variant may lead to milder infection than the delta strain, which swept through nearly every continent within about nine months. Omicron, though, has an unusually high number of mutations on its genome, suggesting that it could be better at infecting people.

“It’s certainly more contagious, no question about that,” said Dr. David Celentano, an epidemiologist and health risk behavior expert at Johns Hopkins Bloomberg School of Public Health. “Anywhere there are a lot of unvaccinated people, there will be more cases. I’d say we have another week before we get some more evidence [about the severity of disease].”

Omicron has moved quickly through the U.S. since it was first identified in California on Dec. 1. It has been found in 19 different states, according to CDC Director Rochelle Walensky, who said on Tuesday that “we expect that number to continue to increase.”