Scientists are on high alert since the WHO on November 26 designated the newly identified SARS-CoV-2 variant B.1.1.529 a variant of concern (VOC), named Omicron, based on the advice of the agency’s Technical Advisory Group on Virus Evolution (TAG-VE). The advisory group felt there was enough evidence that Omicron might be more transmissible, cause more severe disease, or escape immune defenses based on its large number and concerning types of mutations, particularly those on the spike protein that helps the virus bind to and enter cells in order to replicate. The WHO warned on November 29 that Omicron could have “severe consequences” in some parts of the world, urging its member states to speed up vaccinations of high-priority groups and take other steps to prepare. Preliminary evidence shows there may be an increased risk of reinfection with Omicron, meaning people who have infection-induced immunity may be at an increased risk of infection, just as we saw with Delta. Vaccination reduces the risk of severe disease, even with Delta infection, and the same could be true with Omicron. But many uncertainties remain, regarding whether Omicron is more transmissible or capable of immune escape, and public health advice likely will shift as more is learned about the VOC over the coming weeks. Emergence of the Omicron SARS-CoV-2 variant in southern Africa has vaccine manufacturers discussing vaccine effectiveness and the possibility of updating vaccines to make them variant-specific. Omicron has around 50 mutations, and more than 30 of the mutations are located on the viral spike protein that is responsible for entry into host cells. The SARS-CoV-2 spike protein also is one of the primary antibody targets for the immune system. According to some analysis, most of the antibody target sites on Omicron’s spike protein are mutated, and several of those differences could indicate that Omicron is capable of escaping current vaccine formulations. A subset of Omicron’s spike mutations have been previously reported in the Beta and Delta variants, but 26 spike mutations are believed to be unique. Scientists are anticipating a decrease in antibody neutralization of the virus, and doctors in South Africa are reporting reinfections in patients who have already recovered from COVID-19. Pfizer-BioNTech, Moderna, AstraZeneca, and J&J-Janssen—as well as laboratories worldwide—are working to determine how well the current vaccine formulations hold up against Omicron. Data from these experiments are expected within the next 2 weeks. Pfizer-BioNTech and Moderna said they could have variant-specific booster doses ready to ship in about 3 months. It will likely take several weeks before we know if current vaccine formulations are effective against Omicron, but they are expected to continue to help reduce the risk of hospitalization and death due to COVID-19. As a result, primary vaccination and booster doses are recommended for every person who is eligible to receive one. The swift emergence and potential threat of the newly identified Omicron variant of concern (VOC) is being called a “We told you so” moment, as SARS-CoV-2 continues to spread in unvaccinated populations.
CSSE is reporting 48,520,789 positive cases in the U.S. and 779,802 deaths. DOH reported for the week ending November 25, 3,686,860 confirmed cases in Florida with 61,548 deaths.
