The top immunologist in the U.S. says that a fourth dose of a vaccine to battle COVID-19 and various variants that keep appearing may be needed in the near future.
Dr. Anthony Fauci, director of the National Institutes of Allergy and Infectious Disease, said federal health officials are already investigating the possible need for a fourth dose for people who have had the two-shot regimen followed by a booster shot.
Fauci’s warning came after Pfizer CEO Albert Bourla also said a fourth dose may be needed, and maybe faster than Fauci’s timeline. And Fauci said a third shot is now most definitely needed for better protection.
“Certainly, when you want to talk about what optimal protection is, I don’t think anybody would argue that optimal protection is going to be with a third shot,” Fauci said on CNN on Wednesday.
The top immunologist’s declaration came the same day that Pfizer announced that the fully vaccinated — those with two shots — will need a booster shot or their level of protection will drop.
On Wednesday, Pfizer-BioNTech reported that initial results from studies examining how well their vaccine protects against a new coronavirus variant found that a booster shot — on top of a two-dose vaccine regimen — neutralizes Omicron in lab studies.
The pharmaceutical company said that just two shots showed decreased protection in studies, but a booster dose significantly raises protection.
“According to the companies’ preliminary data, a third dose provides a similar level of neutralizing antibodies to Omicron as is observed after two doses against wild-type and other variants that emerged before Omicron,” they said in a press release.
“These antibody levels are associated with high efficacy against both the wild-type virus and these variants. A third dose also strongly increases CD8+ T cell levels against multiple spike protein epitopes, which are considered to correlate with the protection against severe disease. Compared to the wild-type virus, the vast majority of these epitopes remain unchanged in the Omicron spike variant,” the release said.
In plain English, blood samples from people who have had a booster showed “25-fold higher levels of neutralizing antibodies against Omicron compared to blood serum from people immunized with just two doses,” Time magazine reported. “Essentially, the booster brought levels of these virus-fighting antibodies back to those seen after two doses against the original virus strain. More durable immune responses involving T cells were also higher against Omicron after a booster dose.”
“The data very clearly indicate the value of a third dose,” BioNTech CEO and co-founder Uger Sahin said during a briefing discussing the results, according to Time.
“With the data now coming on the Omicron variant, it is very clear that our vaccine for the Omicron variant should be a three-dose vaccine. The best [strategy] now to ensure protection would be to get a booster shot, thereby improving levels of antibodies, [and] improving levels of T cells, which are correlated with better protection against the currently circulating Delta [variant] and which we believe will also translate to better protection against the Omicron variant,” he said.
Early data is showing that Omicron may not be as bad as the original COVID-19, or the variant Delta, according to a report this week. With Omicron, which emerged in South Africa and is spreading rapidly there, the symptoms appear to be less severe.
“Researchers at a major hospital complex in Pretoria reported that their patients with the coronavirus are much less sick than those they have treated before, and that other hospitals are seeing the same trends,” The New York Times reported. “In fact, they said, most of their infected patients were admitted for other reasons and have no Covid symptoms.”
The Times reported that “scientists cautioned against placing too much stock in either the potential good news of less severity,” but cited a new report offering an optimistic view.
After the variant emerged, the World Health Organization (WHO) said Omicron poses a “very high” global risk and could bypass even those who have been vaccinated. The strain is a “highly divergent variant with a high number of mutations … some of which are concerning and may be associated with immune escape potential and higher transmissibility,” the U.N. agency said.
“The overall global risk related to the new variant … is assessed as very high,” WHO said, adding that Omicron “has an unprecedented number of spike mutations, some of which are concerning for their potential impact on the trajectory of the pandemic.”