Center for vaccination against COVID-19 in London. The United Kingdom became the first country to approve a specific revaccination against omicrons.
Mike Kemp/Images via Getty Images
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Mike Kemp/Images via Getty Images
Center for vaccination against COVID-19 in London. The United Kingdom became the first country to approve a specific revaccination against omicrons.
Mike Kemp/Images via Getty Images
The United Kingdom has become the first country to approve vaccine boosters designed to fight the micron variant of COVID-19, paving the way for Britons to get their shots in early autumn.
Moderna’s vaccine approved in the UK is “bivalent”, meaning it is a mixture of two versions of the vaccine: half targeting the original strain of COVID-19 and half a new formulation designed to fight the original variant omicron, also known as as BA.1.
“What this bivalent vaccine gives us is a refined tool in our arsenal to help protect us against this disease as the virus continues to evolve,” Dr June Raine, head of the UK Medicines and Healthcare Products Regulatory Agency, said in a statement. . .
UK researchers have found that the omicron enhancer, made by Moderna, “elicits a strong immune response” against the original strain of the 2020 coronavirus and the original omicron variant that emerged late last year.
What has been approved in the UK is a different shot than the omicron-specific booster that US officials hope to launch this fall.
Here in the US, the FDA has asked vaccine developers to target the omicron subvariants known as BA.4 and BA.5 — the two strains that currently account for the vast majority of cases here — rather than focusing on the original omicron variant that swept the country last winter.
Moderna’s vaccine, approved in the UK on Monday, was less effective against BA.5 – although it still “generates”.[d] good immune response” against this strain, the researchers say.
British regulators also found that the side effects of the bivalent vaccine were similar to those of the original Moderna vaccine – “generally mild and self-limiting” – and that there were no serious safety concerns.
Why does the US want different Omicron boosters?
Moderna’s bivalent booster — along with similar ones made by Pfizer and BioNTech — is more effective against new variants of the virus than the original vaccines.
But these bivalent arrows were designed around the original omicron variant and as a result are less effective against the BA.4 and BA.5.
The original omicron variant emerged in late 2021 and helped fuel a massive wave of infections during last year’s holiday season. Since then, it has mutated into several different sub-variants that have come to dominate the load one by one. The BA.5 subvariant is now dominant in the US, accounting for nearly 90% of all cases.
This rapid shift in the composition of the virus has become a “moving target” for health officials trying to guide vaccine policy, said Dr. Anthony Fauci, the top infectious disease official in the US.
In late June, the FDA, alert to the possibility of another winter outbreak, decided to ask vaccine manufacturers to create a bivalent vaccine targeting BA.4 and BA.5 rather than the original omicron strain.
“Hopefully, it will be close enough to whatever option is developed as we go into the fall and winter,” Fauci told NPR late last month.
When will omicron accelerators be available in the US?
Officials said omicron-specific boosters will be available to Americans sometime this fall.
The US has purchased more than 170 million total doses of Omicron boosters from Pfizer and Moderna. (That’s not enough for all 330 million Americans. But only about two-thirds of Americans complete their initial course of the vaccine, and less than half of those receive a booster shot.)
The regulatory process to help show that vaccines are safe and effective is still ongoing. Officials said they hope to issue a permit for the boosters by mid-September.
Can I get another original booster?
According to CDC guidelines, Americans age 50 and older and some immunocompromised individuals may already receive a second booster shot.
As for others, some experts say that new amplifiers specific to the BA.4 and BA.5 are expected soon enough, and it’s worth the wait.
Most people under the age of 50 who do not have other medical conditions already have some protection. Although the effectiveness of the original vaccine and booster has decreased slightly, they still help, especially in preventing serious infections and hospitalizations. In addition, some estimates suggest that around 80% of Americans have contracted COVID-19, adding natural immunity to the mix.
Also, vaccines may be less effective if they are taken too close together. In general, if you’re young and otherwise healthy, it may be better to wait for a new booster this fall, said Dr. Carlos del Rio, an infectious disease specialist at Emory University.
“If you get the vaccine right now, you won’t respond as well if you get another vaccine that’s so close to this one. There should be time between doses of vaccines,” del Rio told NPR. earlier this month. “In other words, there’s more risk than benefit to getting another booster right now.”
Additional reporting by NPR’s Rob Stein.
