Updated booster shots have bolstered Americans’ defenses against severe Covid, reducing the risk of hospitalization by about 50 percent compared to certain groups vaccinated with the original vaccines, the Centers for Disease Control and Prevention reported in a pair of studies published on Friday.
The research represents the agency’s first look at how the reformulated boosters, tailored to protect against recent Omicron variants, perform in preventing serious consequences of infection with the virus, including emergency room visits and hospitalizations.
Federal health officials are urging Americans to get the updated booster shots, hoping to revive a lagging vaccine campaign. However, so far less than one-fifth of U.S. adults and only one-third of people age 65 and older have received updated injections, reflecting a withdrawal in many parts of the country from more aggressive vaccination campaigns earlier in the pandemic .
New virus variants better able to evade the immune system have gained momentum and Covid cases and hospitalizations have risen in recent weeks. On average, about 375 Americans die each day, a 50 percent increase in the past two weeks. The elderly are particularly hard hit.
The virus has exacerbated the problems facing a healthcare system already strained by flu and respiratory syncytial virus flare-ups after two years of reductions in those infections.
Read more about the coronavirus pandemic
- Free home tests: With the number of cases rising, the Biden administration has restarted a program that has delivered hundreds of millions of tests through the postal service.
- Updated recordings: The Food and Drug Administration has expanded eligibility for the updated coronavirus boosters to children as young as 6 months old.
- Infection: Like a zombie in a horror movie, the coronavirus can persist long after death in the bodies of infected patients and even spread to others, according to two startling studies.
- Pregnant woman: While studies have shown the Covid vaccine to be safe for expectant women, many have avoided the injections, unaware of the risks the virus poses.
Even as federal health officials test and encourage the use of masks in certain settings, precautions have become much less common in practice. Antiviral medication for Covid remains difficult to find for many who are infected.
“We probably won’t see waves of Covid like we’ve seen in the past, which is a good thing, but it doesn’t mean people are still dying and those lives can’t still be saved if we get more injections. in the arms,” said Dr. David Dowdy, an epidemiologist at the Johns Hopkins Bloomberg School of Public Health.
A CDC study released Friday examined how the updated injections protected people from Covid-related emergency room visits and hospitalizations across seven health systems.
The study, which looked at about 15,000 hospital admissions, spanned from mid-September to mid-November, when Covid cases were largely caused by the BA.5 Omicron variant – partially targeted by the reformulated injections.
However, more elusive versions of Omicron known as BQ.1 and BQ.1.1 have since become more common, and it’s not clear how relevant the claims are to the newer variants.
During the BA.5 period, people who received the updated boosters had a 57 percent lower risk of hospitalization compared to unvaccinated people, a 38 percent lower risk compared to people who had recently received doses of the original vaccine, and a 45 percent lower risk of hospitalization. risk compared to people whose last dose of the original vaccine was at least 11 months earlier.
But the CDC’s study did not take into account whether patients had previously been infected with the virus, which may make the updated vaccines appear less effective than they are. And the study didn’t take into account whether certain groups were more likely to receive treatments like Paxlovid, which may have biased the results.
A second study reported on the benefits of updated boosters for older Americans in 22 hospitals from early September to late November.
Among people aged 65 and older, the updated vaccines reduced the risk of Covid hospitalization by 84 percent compared to unvaccinated people, and by 73 percent compared to people who received at least two doses of the original vaccines.
CDC scientists said the higher estimates of vaccine effectiveness in older age groups may reflect a variety of differences in the specific groups of patients being studied.