(CNN) — Since covid-19 vaccines became widely available, there has been a large difference in deaths between the vaccinated and the unvaccinated. But recent Covid deaths are much more spread out as highly transmissible variants take hold, vaccine protection wanes and booster shots stall.
Post-vaccination infections have become more common in recent months, increasing the risk of serious illness or death in vulnerable populations as highly transmissible variants spread. This appears to be especially true of older people in the United States, who were among the first to receive the initial vaccination schedule.
In the second half of September, the peak of the surge in the delta variant of the novel coronavirus, less than a quarter of all Covid-19 deaths were among vaccinated people, federal data show. But in January and February, in the midst of the wave produced by the omicron variant, more than 40% of deaths from covid-19 occurred among vaccinated people.
Covid-19 vaccines have saved millions of lives in the United States since the first dose was administered in December 2020, and the unvaccinated are still much more likely to be hospitalized or die than people who are vaccinated with at least two doses of the Moderna or Pfizer/BioNTech mRNA vaccines or with a single dose of the Johnson & Johnson vaccine.
However, evidence continues to accumulate on the critical importance of booster shots.
Of the vaccinated people who died from Covid-19 in January and February, less than a third had received a booster shot, according to a CNN analysis of data from the US Centers for Disease Control and Prevention. CDC). Overall, the risk of dying from covid-19 remains five times higher for people who have not been vaccinated than for those who have at least the initial vaccination schedule, according to CDC data.
But there is also a significant disparity by level of vaccination: when adjusted for age, people vaccinated with only their initial series face a three times greater risk of death than those who also received a booster dose.
The CDC urges people to be “up to date” on their COVID-19 vaccination, including receiving boosters at the right time, but still defines a person as “fully vaccinated” if they have already received at least the initial vaccination.
But this week, a senior Biden administration official was more direct: All adults need a booster dose.
Vaccination is the best way to protect against covid-19, and protection is most effective with at least three vaccinations, the official said.
Others have emphasized the importance of backup to save lives.
“Hardly anyone in this country should die from Covid” with up-to-date vaccines and appropriate antiviral treatments, Dr. Robert Califf, commissioner of the US Food and Drug Administration (FDA), said on Saturday. English), on CNN Newsroom.
“What we should really be concerned about is getting the necessary reinforcements to keep up, so that with the new variants that we have, we don’t have unnecessary deaths and hospitalizations.”
Boosters Benefit High-Risk Seniors Most
In the first year of the pandemic, before vaccines were available, the vast majority of deaths from covid-19, more than 80%, occurred among people over 65 years of age.
In 2021, especially during the delta surge, the median age of people who died from covid-19 shifted to a lower age range. Fewer than 60% of those who died in September were 65 or older, according to provisional data from the CDC.
But 2022 has been much more like 2020 and the first wave of winter; so far this year, close to three-quarters of all covid-19 deaths have been among older people.
Studies have suggested that the effectiveness of the covid-19 vaccine declines over time. CDC data, released in January, found that receiving the vaccine was 90% effective in preventing hospitalizations during a period when omicron was the dominant variant. By comparison, getting two shots was 57% effective when at least six months had passed since the second shot.
The vast majority of older adults completed their initial vaccination schedule more than a year ago. And although acceptance of booster doses among older adults is higher than in other age groups, fewer than two-thirds of older adults have received a booster dose.
The CDC now recommends a second booster dose for this age group as well, and acceptance is even lower.
CNN’s analysis of CDC data from the past few months suggests that disparities in risk between vaccinated people who get a booster compared to those who just get their initial schedule are more prominent among this vulnerable age group.
Covid-19 deaths are preventable
Daily deaths from covid-19 in the US are down to a fraction of what they were in January and February amid the wave of the omicron variant, but hundreds of people are still dying every day.
Cases are rising in nearly every state right now, and the White House has warned that another surge this coming fall and winter could cause 100 million new cases, raising the potential for more severe illness and loss. tragic.
But experts say we have the tools to ensure infections don’t turn into a tragedy.
Dr. Peter Marks, director of the FDA’s Center for Biological Evaluation and Research, said Monday that getting more Americans vaccinated against Covid-19 could make a big difference as the country heads into the fall and boreal winter.
“It’s really important that we try to get half, or a little more than half, of Americans who have only gotten two doses to get that third dose,” he said. “That can make a difference going forward, and in particular it can make a difference now that we’re heading into another wave of Covid-19.”
— Naomi Thomas, Jen Christensen and Elizabeth Cohen contributed reporting.