Looks like it might not be over yet.
Many of the same epidemiologists who have breathed a sigh of relief over Omicron’s relatively low death rate are anticipating that the next lineage might be much worse.
Fretting over a possible future lineage that combines Omicron’s extreme transmissibility with the severity of, say, the previous Delta lineage, experts are beginning to embrace a new public health strategy that’s getting an early test run in Israel: a four-shot regimen of messenger-RNA vaccine.
Omicron features around 50 key mutations, some 30 of which are on the spike protein that helps the virus to grab onto our cells.
Some of the mutations are associated with a virus’s ability to dodge antibodies and thus partially evade vaccines. Others are associated with higher transmissibility. The lineage’s genetic makeup pointed to a huge spike in infections in the unvaccinated as well as an increase in milder “breakthrough” infections in the vaccinated.
Assuming the decoupling (of hospitalization and death with infection) is happening, experts attribute it to two factors. First, Omicron tends to infect the throat without necessarily descending to the lungs, where the potential for lasting or fatal damage is much, much higher. Second, by now, countries have administered nearly 9.3 billion doses of vaccine—enough for a majority of the world’s population to have received at least one dose.
All that is to say, Omicron could have been a lot worse. Viruses evolve to survive. That can mean greater transmissibility, antibody-evasion or more serious infection. Omicron mutated for the former two. There’s a chance some future Sigma or Upsilon lineage could do all three.
When it comes to viral mutations, “extreme events can occur at a non-negligible rate, or probability, and can lead to large consequences,” Michael said. Imagine a lineage that’s as transmissible as Omicron but also attacks the lungs like Delta tends to do. Now imagine that this hypothetical lineage is even more adept than Omicron at evading the vaccines.
That would be the nightmare lineage. And it’s entirely conceivable it’s in our future. There are enough vaccine holdouts, such as the roughly 50 million Americans who say they’ll never get jabbed, that the SARS-CoV-2 pathogen should have ample opportunities for mutation.
“As long as we have unvaccinated people in this country—and across the globe—there is the potential for new and possibly more concerning viral variants to arise,” Aimee Bernard, a University of Colorado immunologist, told The Daily Beast.
Israel, a world leader in global health, is already turning that expectation into policy. Citing multiple studies that showed a big boost in antibodies with an additional dose of mRNA and no safety concerns, the country’s health ministry this week began offering a fourth dose to anyone over the age of 60, who tend to be more vulnerable to COVID than younger people.