Looking around at all those uncovered faces, you may not realize it, but there are still a lot of unique coronaviruses out there. And the virus appears to be evolving at a quicker rate than ever before, resulting in an increasing number of infectious variants and subvariants.
Most patients infected with COVID-19 will not become very ill and will recover within weeks. If you have your COVID-19 vaccination on time, including a booster dose, your chances of being sick enough to require hospitalization are greatly reduced.
COVID Variants Are Cracking the Code to Our Immunity
The emergence of SARS-CoV-2 does not necessarily imply that there would be large increases in infections, hospitalizations, or fatalities. At least not for very long or everywhere.
But it emphasizes an unpleasant truth: the epidemic isn’t ended, despite the easing of COVID restrictions in most countries that aren’t China and despite many people’s want to move on from the anguish and uncertainty of the last two years. The virus is still evolving.
The most transmissible subvariants are the most recent ones. Last month, BA.4 and BA.5, both Omicron children, first appeared in South Africa. Around the same period, BA.2.12 and the similarly related BA.2.12.1 appeared in New York.
Omicron strains BA.4 and BA.5 are 10% more infectious than their direct ancestor, the BA.2 strain. The bacteria BA.2.12 and BA.2.12.1 are 25% more contagious than BA.2.12. Only a few months after BA.2 became dominant, BA.4, BA.5, BA.2.12, and B.2.12.1 are swiftly becoming prevalent in their respective origin regions. BA.2 out-competed and displaced its own parent, BA.1, just a few months after BA.1 became dominant.
In other words, substantial new subvariants appear to be approaching us at an increasing rate. In that way, the virus may appear to be winning a genetic lottery. The virus is growing increasingly transmissible when it encounters a semi-permeable barrier of antibodies from vaccinations and previous infection.
Immune pressure will “raise the pace of selection of those more suited variations that are already circulating in the population,” according to Edwin Michael, an epidemiologist at the University of South Florida’s Center for Global Health Infectious Disease Research. “As a result, new variation cascades will develop and propagate more often in the host population.”
However, this cascade of variations is one of the costs of our population-wide immunity. It’s impossible to have the latter without some of the former. So, while COVID may appear to be succeeding, its genetic gains may be temporary.
Last year, Niema Moshiri, a geneticist at the University of California, San Diego, told The Daily Beast that every COVID infection should be viewed as a gambler playing a slot machine. Moshiri noted that every two weeks, each infection tends to develop two mutations. Alternatively, the virus gets two pulls on the lever every month, hoping to hit the genetic jackpot and gain a new edge over other viruses–as well as a new means to infect its host.
“What if 50 million people all pulled the slot machine levers at the same time?” Moshiri inquired. “We anticipate at least one individual hitting the jackpot really fast.” Now substitute ‘clinically significant SARS-CoV-2 mutation’ for the slot machine, and you have the scenario we’re in.”
To fill out the metaphor, add a growing sense of urgency on the side of the virus as immunity rises all around it. The innovative coronavirus is playing the slots with progressively grimmer intent as it senses threats all around it.
There have never been less than several million active COVID cases throughout the last 30 months of viral waves and crashes. Tens of millions of people were infected at the same time during the greatest outbreaks in early 2021 and early 2022. Given the virus’s rapid mutation rate, it’s no surprise that the virus has created a continual stream of substantial new variants—the technical word is “lineage.”
There was Delta, the more virulent lineage that was responsible for the biggest waves of diseases in 2021 when much of the globe was still waiting for viable medicines and vaccinations. Scientists in Botswana and South Africa discovered the first examples of a new lineage, Omicron, in late 2021.
Omicron is more contagious than Delta due to mutations in the spike protein, which helps the virus grasp onto and infect human cells. On Jan. 19, the deadliest day of the Omicron outbreak, authorities recorded 4 million new illnesses in only 24 hours. That’s four times the number of instances they recorded on the deadliest days of the Delta waves in January and April 2021.
Because of changes in the spike protein, which helps the virus latch onto and infect human cells, Omicron is more infectious than Delta. Authorities documented 4 million new cases in barely 24 hours on Jan. 19, the bloodiest day of the Omicron outbreak. That’s four times the number of times they saw during the Delta waves’ bloodiest days between January and April 2021.
When you add in natural antibodies from hundreds of millions of previous illnesses, the human species’ immune system appears very formidable. Breakthrough infections are common, but the antibodies are quite effective in preventing the virus from causing serious disease or death.
As Omicron became dominant, cases increased dramatically, but mortality did not. On Feb. 9, the bloodiest day of the Omicron surge, 13,000 people were killed worldwide–5,000 less than on Jan. 20, 2021, the worst day of Delta.
COVID’s development has come to define itself as we fumble through the third year of the epidemic, with more cases but fewer fatalities, a pattern epidemiologists’ term “decoupling.” There are hints that decoupling may get much more acute. After all, the immunity that leads to decoupling encourages a virus to evolve more swiftly, resulting in increasingly transmissible lineages.
Immunity promotes mutants, which can boost immunity by seeding antibodies from minor infections. Antibodies and viral lineages are the result of this escalating positive feedback loop.
In the absence of the new coronavirus achieving “self-extinction” by running itself into a genetic corner, a rising gap between infections and fatalities could actually be the best-case situation. When it comes to respiratory viruses, many researchers believe that an evolutionary dead end is wishful thinking. Jesse Bloom, a scientist at the Fred Hutchinson Cancer Research Center in Washington State, told The Daily Beast, “I think self-extinction is vanishingly remote.”
The bad news is that we’ll likely have to adapt to increasingly more infectious SARS-CoV-2 variations and subvariants appearing at an increasing rate. The good news is that we are prepared. BA.4, BA.5, BA.2.12, and BA.2.12.1 have the potential to bypass human vaccine-induced and natural antibodies–what specialists refer to as “immune escape.”
Immune evasion does not imply absolute immunity. Antibodies from natural sources and vaccines are still effective. They’re the reason the fundamental Omicron lineage’s instances and fatalities separated. They’re also the reason Omicron’s nasty little progeny are likely to decouple. “The mutations don’t appear to be as pathogenic as Delta,” Stephanie James, the director of a COVID testing lab at Regis University in Colorado, told The Daily Beast.
That is to say, in the next months, expect to hear a lot about new lineages and sub lineages as they emerge and become dominant at an increasing rate. Even if you’ve been vaccinated and boosted and maybe have antibodies from previous infections, don’t be shocked if you get one of them.
Don’t panic for the new Covid variant news. If you keep up with your vaccines, you should be OK.
Unless, of course, the development of SARS-CoV-2 takes a hazardous turn. With all of the main lineages and sub lineages we’ve observed in the last two years, immune escape has been rather low. That doesn’t rule out the possibility of the virus evolving to overcome strong immunological resistance. If mutations are like slots for pathogens, and a jackpot is a new variant, then a variant that can punch through our antibodies is a mega-jackpot.
Everything changes if the virus ever wins that bet.