A rising river of international information regarding a new SARS-CoV-2 variant first recognized in southern Africa, now reported on three continents and triggering travel bans, led WHO on Nov. 26 to convene an emergency meeting, name the virus “Omicron” and label it a “Variant of Concern (VOC).”
This virus has many more mutations (32) in the spike protein than any prior variants, as well as mutations outside the spike protein. In addition to this quantity of mutations is the quality of some of these 32 mutations in terms of their being linked in prior variants with increased transmission or evasion of some antibodies induced by infection or vaccines, or some monoclonal antibodies. For persons around the world who are unable or unwilling to be vaccinated, this Omicron variant could increase the risk of infection even more than the delta variant, if in fact Omicron is more contagious than delta.
The preliminary information suggests this virus could be more contagious than the Delta virus (e.g., in Gauteng province, South Africa) and is likely to at least partially evade immunity from some vaccines and immunity from prior infection. The spike protein of the original virus of 2019 is the central part of currently deployed global COVID-19 vaccines.
Two or more weeks are anticipated to test in vitro antibody and T-cell response of current “first generation” vaccines against this highly mutated Omicron variant. If immune evasion to vaccines is proven in vitro, then valuable time will have been lost if only afterwards work starts on a new “second-generation” vaccine using the 32-mutation spike protein of Omicron.
Media reports of some vaccinated persons being infected with Omicron among those diagnosed in Hong Kong, Botswana and Israel have appeared. Laboratory studies are likely being undertaken to assess the impact of the number and timing of vaccinations, and the vaccine effect on the viral load and clinical severity of Omicron infections.
Thus, “Omicron” warrants starting to develop new vaccines immediately (Nov. 26) using the “Omicron” spike protein in parallel with in vitro testing of this variant against current vaccines. There is no time to lose for people and economies, not only of southern Africa but of our pandemic world.
Editor’s note: This post was written on Nov. 26 but is being posted on Nov. 29 due to the U.S. Thanksgiving holiday.