Will the Pfizer and Moderna vaccines work against the new coronavirus variants?
By now, you’ve probably already seen the reports on the emergence of new, more contagious variants of SARS-CoV-2, the virus that causes COVID-19. And, like me, you’ve probably stared at the ceiling after reading them, asking, “Really, universe? Really?”
As exasperating as this might all seem, though, we don’t need to be alarmed about the COVID-19 vaccines' efficacy against these new variants, according to the infectious disease experts I interviewed. At the same time, it’s still important to get vaccinated when you can, and not let your guard down when it comes to masking, social distancing, and other precautions.
But before we dig into some expert analyses, let’s pan out a little: Viruses mutate, forming new variants, all the time. In many cases, these variants are NBD, but scientists have turned their focus to three that seem to spread faster and more easily than others. These include a variant first observed in the U.K. last September, which has since been identified in many other countries, including the U.S. One variant has emerged in South Africa, and another in Brazil. The former hasn’t been detected in the U.S. so far, but the latter was seen in a Minnesota resident on Monday.
The variants share a mutation that alters a certain region of the spike protein — which the virus uses to enter the body’s cells — among numerous other mutations, including some more on the spike protein, according to The Scientist.
“The main concern is the contagiousness of those strains,” Jarod Fox, an infectious disease specialist at Orlando Health, tells Mic. “They don’t seem to be any more deadly, but the concern is, the more infections you have, the more deaths you’re going to have.” In other words, the death rate will likely stay the same, but would be out of a larger total number of infections. And more infected people in hospitals could overburden the health system, which can also lead to more deaths, including among those with heart attacks and other issues besides COVID-19.
To test the efficacy of the vaccines currently available in the U.S. — one made by Pfizer-BioNTech, the other by Moderna — against SARS-CoV-2 variants, scientists conducted lab studies with blood samples from vaccinated individuals, explain Fox and Shobha Swaminathan, associate professor and principal investigator for the Moderna Phase 3 trial at Rutgers New Jersey Medical School. Remember that the vaccines work by triggering the production of antibodies against SARS-CoV-2. The studies looked at whether the antibodies vaccinated people’s bodies had made could neutralize the variants, that is, prevent them from infecting cells.
Based on preliminary data from these studies, both vaccines “maintained their stated efficacy” against the variant that had emerged in the U.K., Fox says. Moderna reports reduced efficacy against the one that had emerged in South Africa, but not to levels that warrant serious concern, Swaminathan says. The company believes the efficacy is still “over the minimum requirement for the vaccine to work.”
To play it safe, it’s developing a booster shot against this variant and another against new mutations in general. Pfizer hasn’t released efficacy data for this variant yet, but Fox imagines that they'd resemble Moderna's, since its vaccine is similar . Neither company’s published efficacy data for the variant first detected in Brazil.
“The thing is, variants emerging over time is natural,” Swaminathan says. “That’s what we would expect of any virus.” She adds that the vaccines spur the production of antibodies that target the entire length of the SARS-CoV-2 spike protein; even if there are changes in one or two places, the diversity of these antibodies should ensure that the vaccines will still offer protection.
Swaminathan and Fox agree that even if the Pfizer and Moderna vaccines show decreased efficacy against SARS-CoV-2 variants, it’s still crucial that people get vaccinated. To put it in perspective, the COVID-19 vaccines had a 95% efficacy rate in clinical trials — whereas the seasonal flu vaccine is only around 60% effective at best, Swaminathan says.
“Even if [COVID-19] vaccine effectiveness drops a couple percentage points, it’s still more effective than a flu shot,” she tells Mic. “I think we should be aware of these things and be on the lookout and monitor to ensure continued efficacy, but I’m not alarmed.” She adds that none of the SARS-CoV-2 variants appear to be completely resistant to the vaccines — that’s very different from the vaccines having reduced efficacy against them.
Neither she nor Fox believe we need to take any new public health precautions in light of these variants, just “be extra vigilant about following the rules already out there,” she says: Wash your hands, practice social distancing, and remember that “household” contacts means, literally, only people in your household.
And wear a mask — correctly. (That means not pulling it down whenever you speak to someone, Swaminathan says.) Double-masking can create more barriers against the virus, although it might make more sense in certain situations, like, say, shopping at a supermarket.
In an interview with WTOP News, Anthony Fauci noted that the new variants only underscore the importance of vaccination. “When you prevent a virus from easily … replicating, then you prevent it from mutating. So, if you don’t want to see a virus takeover in this country, then suppress all the virus that’s here.”
While we'll want to keep an eye on any changes in SARS-CoV-2, it’s also worth recognizing that the COVID-19 vaccines are feats of modern medicine, which will likely still protect us from these variants — we just need to roll them out faster.