The race against COVID-19 has taken a new turn. Mutations are rapidly popping up, and the longer it takes to vaccinate people, the more likely it is that a variant that can elude current tests, treatments and vaccines could emerge.
The coronavirus is becoming more genetically diverse, and health officials say the high rate of new cases is the main reason. Each new infection gives the virus a chance to mutate as it makes copies of itself. And that threatens to undo the progress made to control the pandemic.
The federal Centers for Disease Control and Prevention says a new version first identified in the United Kingdom could become dominant in the United States by March. It doesn’t cause more severe illness. But it will lead to more hospitalizations and deaths because it spreads so much more easily, according to the CDC.
“We need to do everything we can now … to get transmission as low as we possibly can,” said Harvard University’s Dr. Michael Mina. “The best way to prevent mutant strains from emerging is to slow transmission.”
So far, vaccines seem to remain effective. But there are signs some of the new mutations might undermine tests for the virus and reduce the effectiveness of antibody drugs.
“We’re in a race against time” because the virus “may stumble upon a mutation” that makes it more dangerous, said Dr. Pardis Sabeti, an evolutionary biologist at the Broad Institute of MIT and Harvard.
Younger people might be less willing to wear masks, shun crowds and take other steps to avoid infection because the current strain doesn’t seem to make them very sick, but, “in one mutational change, it might,” said Sabeti, who documented a change in the Ebola virus during the 2014 outbreak that made it much worse.
MUTATIONS ON THE RISE
It’s normal for viruses to acquire small changes — mutations — in their genetic alphabet as they reproduce. Ones that help the virus flourish give it a competitive advantage and thus crowd out other versions.
In March, a couple of months after the coronavirus was discovered in China, a mutation called D614G emerged that made it more likely to spread. It soon became the dominant version.
Now, after months of relative calm, “We’ve started to see some striking evolution” of the virus, biologist Trevor Bedford of the Fred Hutchinson Cancer Research Center in Seattle wrote on Twitter: “The fact that we’ve observed three variants of concern emerge since September suggests that there are likely more to come.”
One, first identified in the United Kingdom, quickly became dominant in parts of England. It now has been reported in at least 30 countries, including the United States.
Soon afterward, South Africa and Brazil reported new variants, and the main mutation in the version identified in Britain turned up in a different version “that’s been circulating in Ohio … at least as far back as September,” said Dr. Dan Jones, a molecular pathologist at Ohio State University.
This might reflect the virus acquiring similar mutations independently as more infections occur, Jones said.
That also suggests that travel restrictions might be ineffective, Mina said.
TREATMENT, VACCINE, REINFECTION RISKS
Some lab tests suggest the variants identified in South Africa and Brazil could be less susceptible to antibody drugs or convalescent plasma, antibody-rich blood from COVID-19 survivors — which help people fight off the virus.
Government scientists are “actively looking” into that possibility, according to Dr. Janet Woodcock of the U.S. Food and Drug Administration, and encouraging development of multi-antibody treatments rather than single-antibody drugs to have more ways to target the virus in case one proves ineffective.
Current vaccines induce broad enough immune responses that they should remain effective, many scientists say. Enough genetic change eventually could require tweaking the vaccine formula, but “it’s probably going to be on the order of years if we use the vaccine well rather than months,” according to Dr. Andrew Pavia of the University of Utah.
Health officials also worry that, if the virus changes enough, people might get COVID-19 a second time.
WHAT TO DO
“We’re seeing a lot of variants, viral diversity because there’s a lot of virus out there,” and reducing new infections is the best way to curb it, said Dr. Adam Lauring, an infectious diseases expert at the University of Michigan.
Loyce Pace, who heads the nonprofit Global Health Council and is a member of President-elect Joe Biden’s COVID-19 advisory board, said the same precautions scientists have been advising all along “still work, and they still matter.”
“We still want people to be masking up,” she said. “We still need people to limit congregating with people outside their household. We still need people to be washing their hands and really being vigilant about those public health practices, especially as these variants emerge.”