Reinfections More Likely With New Coronavirus Variants, Evidence Suggests

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Workers check oxygen tanks at a hospital in Manaus, Brazil. Severe oxygen shortages as a second coronavirus wave is surging have prompted local authorities to airlift patients to other parts of Brazil.

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Goats and Soda
The Worst Of COVID-19 Should Be Over For 1 Hard-Hit Brazilian City. But It’s Not

Last week, scientists in Brazil detected a new genetic variant of coronavirus that has been circulating in Manaus since at least December and is likely fueling the second surge. Called P1, the variant has a set of about 20 mutations, including three mutations that are particularly concerning. These mutations could make the virus more infectious and could possibly decrease the efficacy of vaccines against the variant.

There’s growing evidence that new genetic variants of the coronavirus — specifically, the ones circulating in South Africa and around Manaus, Brazil — may be capable of evading the body’s immune system. Both variants have three of the same mutations in the region of the virus that binds to human cells and to some antibodies (specifically, K417N, E484K and N501Y). The mutations decrease some antibodies’ ability to recognize and neutralize the virus, a team of scientists reported Tuesday in a study on the South African variant. Specifically, the scientists looked at whether the variant from South Africa could be neutralized by blood plasma, which contains antibodies, taken from people who had been infected with older versions of the virus. In 21 of the 44 samples, the new variant was resistant to neutralization by the plasma serum.

And thus, mutations in these new variants could make it easier for some people to get COVID-19 a second time, says virologist Ravi Gupta at the University of Cambridge. «We know that you can get reinfected even with the same version of the virus, he says. The mutations could put even more of a dent in the barrier of resistance.

No knows yet how common these types of reinfections will be, Gupta says. They could be rare. But reinfections could increase as time goes on — and a person’s immunity to the virus naturally wanes, he adds.

«The bottom line is that we don’t know yet what’s causing the surge in Manaus, says virologist Jeremy Luban at the University of Massachusetts Medical School. «The scenarios that people are worried about are plausible, and they’re a cause for concern.

But Dr. Lacerda from Manaus believes reinfections are indeed behind the second outbreak there, and he’s concerned reinfections will fuel deadly surges in other cities around Brazil if widespread vaccinations don’t occur quickly. Vaccinations will still work, he believes, but the efficacy could be decreased. And he thinks that if people had been vaccinated earlier the surge wouldn’t have been so bad.

«Manaus is just a lighthouse that is pointing to what could happen in the rest of the country, he says. And perhaps what could happen in the rest of the world.

NPR Correspondent Philip Reeves contributed reporting for this story.