The New Delta Strain Reveals the Shakiness of Our Covid-19 Situation
The longer the wider world remains unvaccinated, the greater the risk that a devastating new variant will emerge
In a letter recently obtained by The Guardian newspaper, more than 100 former presidents and heads of state urged the leaders of the world’s wealthiest countries to do much more — to commit more money, in particular, but also more aid and resources — toward making and distributing vaccines across the globe.
“No one anywhere is safe from Covid-19 until everyone is safe everywhere,” the letter’s signatories wrote, according to The Guardian.
That’s not just lofty talk, and it’s not just a plea for the sake of the unvaccinated. That is cold reality.
Apart from the deadly threat that the virus poses to those it infects, there is the coincident threat that a new vaccine-resistant strain of SARS-CoV-2 could emerge.
“Infected human beings are factories that produce billions and billions of virus particles,” says John Swartzberg, MD, clinical professor emeritus of infectious diseases and vaccinology at the University of California, Berkeley. “And as those are produced, mistakes will happen,”
Those “mistakes” are variants. Fortunately for us, SARS-CoV-2 is a relatively stable pathogen. Even when mistakes occur, 99.99% of them peter out quickly because they don’t confer any advantage on the virus.
But as we’ve already seen, when millions of people around the globe are infected, what can seem like a minuscule risk becomes a statistical likelihood. Already, there’s concern that the new “Delta” strain could weaken our tenuous defenses.
Experts first identified the Delta strain, also known as the B.1.617 variant, late last year in India. Since then, researchers have discovered at least three subtypes of the variant, which are now dominant in the U.K. and have begun to turn up in the U.S.
Troublingly, there’s evidence that the most effective vaccines we have may not work as well against the newer strain.
A study published June 3 in The Lancet found that the Pfizer-BioNTech vaccine tends to produce lower levels of virus-stopping antibodies when exposed to the Delta variant than when pitted against the older variants it was designed to block. Meanwhile, infection rates have roughly doubled in the U.K. during the past month, an alarming shift that some experts say is at least partly driven by the new strains.
So far, there’s little real-world evidence that fully vaccinated individuals are more likely to get sick or die if exposed to the Delta variants. But as long as billions of people around the world remain unvaccinated, there is a risk that a new and vaccine-resistant virus subtype will emerge and cast us back into the dark days of 2020.
There’s even a risk — albeit small — that a new and dangerous variant may sprout in someone who is vaccinated.
Swartzberg explains that when vaccines, antibiotics, or other infection-targeting countermeasures don’t work well they can in some cases encourage pathogen resistance or the emergence of a new strain that could be more difficult to treat or manage than its predecessor. “But it’s a far less likely scenario than a variant emerging in an unvaccinated individual,” he says.
This risk shouldn’t be confused with internet conspiracy theories that say vaccines encourage mutations. When they work well, they don’t. And for now, the vaccines we have work extremely well — better than most experts dared to hope.
But this is yet another incentive to do all that we can to promote vaccine coverage — both here and abroad — before new, problematic variants have the chance to emerge.
“Even from a purely selfish perspective, those of us who are vaccinated should want to ensure the whole world is vaccinated as quickly as possible,” Swartzberg says. “We’re really in a race with this virus, and it’s trying to survive just like we are.”