On Dec. 14, a new NIH Director’s Blog was posted entitled, “Latest on Omicron Variant and COVID-19 Vaccine Protection.”
The blog states that “There’s been great concern about the new Omicron variant of SARS-CoV-2, the coronavirus that causes COVID-19. A major reason is Omicron has accumulated over 50 mutations, including about 30 in the spike protein, the part of the coronavirus that mRNA vaccines teach our immune systems to attack. All of these genetic changes raise the possibility that Omicron could cause breakthrough infections in people who’ve already received a Pfizer or Moderna mRNA vaccine.”
Further, “So, what does the science show? The first data to emerge present somewhat encouraging results. While our existing mRNA vaccines still offer some protection against Omicron, there appears to be a significant decline in neutralizing antibodies against this variant in people who have received two shots of an mRNA vaccine.”
The blog goes on to explain that studies show people who get a booster shot may be better protected. Although the data are new, it is suggesting that getting a booster will help protect those already vaccinated from the Omicron variant during the winter months.
“Very recently, real-world data from the United Kingdom, where Omicron cases are rising rapidly, are providing additional evidence for how boosters can help,” the blog continues. “In a preprint, Andrews et. al showed the effectiveness of two shots of Pfizer mRNA vaccine trended down after four months to about 40 percent. That’s not great, but note that 40 percent is far better than zero. So, clearly there is some protection provided.”
Moreover, “Most impressively (as shown in the figure to the right) a booster substantially raised that vaccine effectiveness to about 80 percent. That’s not quite as high as for Delta, but certainly an encouraging result. Once again, these data show that boosting the immune system after a pause produces enhanced immunity against new viral variants, even though the booster was designed from the original virus. Your immune system is awfully clever. You get both quantitative and qualitative benefits.”
The blog adds that scientists around the world are closely monitoring Omicron’s severity, and while it appears to be highly transmissible, it is still too early for “rigorous conclusions,” and the initial research indicates the variant may be milder than Delta—Delta is currently the dominant strain in the U.S.
“But there’s still a tremendous amount of research to be done that could change how we view Omicron,” the blog states. “This research will take time and patience.”
The blog concludes that “What won’t change, though, is that vaccines are the best way to protect yourself and others against COVID-19. (And these recent data provide an even-stronger reason to get a booster now if you are eligible.) Wearing a mask, especially in public indoor settings, offers good protection against the spread of all SARS-CoV-2 variants. If you’ve got symptoms or think you may have been exposed, get tested and stay home if you get a positive result. As we await more answers, it’s as important as ever to use all the tools available to keep yourself, your loved ones, and your community happy and healthy this holiday season.”
