As the past year has progressed, it has become clear that we are not living in quite the same pandemic that sent the world into lockdown nearly two years ago. Mutations in the genetic code of the SARS-CoV-2 virus that causes the COVID-19 disease have created new variants with diverse impacts. In response to the evolution of the virus, our public health strategies have also changed—but how can we expect the virus to evolve in the new year and beyond, and how can we continue to adapt our response?
Variants of concern: causes and responses
Of the thirteen named variants of the SARS-CoV-2 virus, the ones you’re most likely to have heard about are those classified by the WHO as variants of concern (VOCs)—Alpha, Beta, Gamma, Delta, and Omicron. These are variants that have been proven to cause a significant global health risk. (The Greek letters from Epsilon to Mu are accounted for by former or current variants of interest, which have not been shown to be global health risks, with Nu and Xi skipped).
The five VOCs have had major impacts around the world during the past year. In Canada and other countries, Alpha drove 2020-2021’s massive winter wave. Beta caused outbreaks around the world later in 2021, especially in South Africa. Since its emergence in early 2021, Gamma remains mostly contained to Brazil. The Delta variant became the dominant strain globally as it spread between countries in mid to late 2021.
Finally, the highly mutated and extremely contagious Omicron variant—first identified in South Africa in November 2021—is currently driving a greater spike in cases worldwide than ever before. In Canada, this came in the form of a fifth wave that saw us closing out 2021 with a record-shattering 45,876 new confirmed COVID-19 cases on December 31.
Most of the mutations that make each of these variants so infectious are contained in the gene that codes for the coronavirus’s spike protein. This is the structure that protrudes from the viral particle, giving it its characteristic “crown” appearance. The spike allows the virus to recognize and attach to human cells, leading to invasion and infection.
When a human survives infection with COVID-19 or is vaccinated against the disease, the spike protein is key to creating immunity. After invasion of a virus covered in spikes (infection), or delivery of a small dose of harmless, isolated spikes to our blood circulation (vaccination), our immune systems learn to recognize this foreign protein and create defenses against it. Then, when the spikes appear on the shell of a virus in the future, our immune systems are primed and ready to attack it.
Until Omicron, two doses of vaccine sufficed to prime our immune systems from VOCs. Though the vaccines remain effective against severe disease, health organizations such as Ontario’s Ministry of Health are recommending additional booster doses to counter Omicron’s immune evasion. With further, similar mutations inevitably lying ahead, it’s becoming increasingly clear that we won’t be through with COVID-19 vaccines for a long time—if ever.
The future of COVID-19
While infection and inoculation both grant our immune systems defenses against COVID-19, SARS-CoV-2 can develop mutations that allow it to evade new defenses and infect more human host cells, replicate faster, and spread further. As we upgrade our immune defenses with more vaccines, we might expect that COVID variants capable of surviving our vaccination efforts will become meaner, more infective, and more severe than before. So, does fighting back mean backing this highly mutable virus into a corner, until it turns into a super-disease that can’t be stopped? Is it possible that our well-intentioned vaccination campaigns will backfire and take COVID-19 from a pandemic to an extinction event?
Put simply: not really. Firstly, viruses rely on their hosts generally staying well enough to be around others, lest transmission becomes impossible; an overly aggressive mutant would be unable to propagate if it was confining most of its hosts to bed. Secondly, there are basic biological limits to viral transmissibility, replication rate, and virulence. Thirdly, some immunity-dodging mutations could carry evolutionary drawbacks; for instance, infection with multiple spike protein mutants could eventually give our immune systems the ability to recognize a wide range of spike proteins, providing much more robust immunity for us down the line.
So, no—we aren’t looking at an apocalypse or an extinction event. Nor will SARS-CoV-2 die out completely. More likely, we will see COVID-19 become an endemic disease, persisting in a stable state with outbreaks occurring every now and then.
Opinion is mixed on what the specifics could look like. Outbreaks could resemble seasonal influenza, respiratory syncytial virus (which primarily affects young children), other seasonal coronaviruses, or even the measles. The rate of SARS-CoV-2 mutation could require updated vaccines every six months or every five years, and inoculation once or 80 times in a human’s lifetime. The disease could be clinically mild or severe, and the phenomenon of “long COVID” (a chance of long-term effects in the brain, heart, or lungs) may change, too.
There’s a huge range of possibilities—it all depends on the mutants that emerge in the future. If Omicron and its mutant “children” continue to reign supreme, some evidence suggests that the pandemic could be milder in its respiratory attack and cause lower individual risks of severe illness or death. However, much remains unknown about Omicron, and it’s impossible to know whether its dominance may be usurped by yet another new VOC.
What we can do
Much of the virus’s future is up to chance, but some of it can be influenced by humankind. Though a lot has changed in the past year, the single most important way we can combat COVID-19 is the same as it was in 2021: mass vaccination. Unfortunately, vaccine inequity between wealthier and lower-income countries means that the virus has a huge playground (in the form of about 40 percent of the world’s population) to gain advantages in the evolutionary arms race. Global governmental failures to clarify and implement consistent, effective public health measures and guidelines have also taken a toll, providing more space for the virus to mutate freely.
Promisingly, though, the cheap, patent-free CORBEVAX vaccine newly developed in Texas will soon be available in millions of doses in India and possibly other countries. More vaccines remain in development. Furthermore, as calls for patent waivers mount, it’s possible—though not necessarily likely—that larger vaccine developers could have a change of heart.
Despite the challenges presented by inequality and inefficiency, there is hope for the future. Though it’s impossible to say for sure where COVID-19 is headed, we do know that the pandemic in its current form will not last forever. And if you’re looking to do your part to speed up the process, there’s one clear step that all of us can take: get the vaccine.
