From the Washington Post January 26, 2021 by Marisa Lati and Angela Fritz

Viruses are always mutating and taking on new forms. The coronavirus has thousands of variants that have been identified. But several, including the U.K., South Africa and Brazil variants, are highly transmissible and have sparked concerns that vaccines may be less effective against them.

The same protective measures that have warded off the virus throughout the pandemic — maintaining social distance, wearing masks and washing our hands — are even more critical in the face of more transmissible variants.

Brazil variant (P.1)

Where and when was it discovered?

Sequencing studies found the variant in Brazil, mainly in Rio de Janeiro, as early as July. Researchers in Japan discovered it in travelers from Brazil this month.

Where is it now?

It has been confirmed in Brazil, Peru, Germany, South Korea and Japan, among other places. On Monday, Minnesota health officials confirmed the first U.S. case of the Brazil variant in a resident with recent travel history to Brazil.

What makes it different?

The variant has more than a dozen alterations, several of which are found on the virus’s spike protein, which binds the virus to a cell. Because of that, researchers think the strain is probably more transmissible. There is also some early evidence that antibodies might not recognize the P.1 variant, which could lead to reinfection.

Will vaccines work?

There’s no strong evidence right now suggesting that vaccines won’t work against the Brazil variant. However, scientists have raised the possibility that this variant can evade antibodies, which would impact the current vaccines’ effectiveness.

The U.K. variant (B.1.1.7)

Where and when was it discovered?

This variant was first found in the United Kingdom, specifically in London and the nearby county of Kent, in September. It is sometimes referred to as the “Kent” variant. It has been spreading rapidly in Britain, Denmark and Ireland since December.

Where is it?

Dozens of countries, including the United States, have seen infections from this variant of the virus. The Centers for Disease Control and Prevention released a model forecast in early January that indicated the variant could become the dominant strain in the United States by some point in March.

What makes it different?

The U.K. variant appears more transmissible than the more common strain. British Prime Minister Boris Johnson also suggested for the first time in January that this strain may be more lethal than previous mutations.

Will vaccines work?

The scientific consensus is that the vaccines will remain effective against this mutation because those inoculations provoke an array of neutralizing antibodies and other immune-system responses. Biotechnology companies Pfizer and Moderna have said their vaccines appear to work against this variant.

The South Africa variant (501Y.V2)

Where and when was it discovered?

This mutation, also referred to as B1.351, was found in South Africa in early October and announced in December, when the country’s health minister said the strain seemed to affect young people more than previous strains. This variant may have contributed to a surge of infections and hospitalizations across South Africa.

Where is it?

This mutation has been identified in more than two dozen countries, including Canada, Australia and Israel, but not in the United States.

What makes it different?

This mutation shares some similarities to the U.K. variant and, like that strain, appears to be more transmissible. There is no evidence that it is more lethal. Scott Gottlieb, former director of the Food and Drug Administration, has suggested that this variant might be more resistant to antibody therapies.

Will vaccines work?

The vaccines may have a diminished impact against this variant, but they probably will still be effective, top infectious-diseases expert Anthony S. Fauci said in January. Moderna has said its vaccine protects against the South Africa variant, with an important caveat: The vaccine-elicited antibodies were also less effective at neutralizing this mutation in a laboratory dish.

Ravindra Gupta, a professor of clinical microbiology at the University of Cambridge, found in a study of older adults that the immune response triggered by the Pfizer vaccine was modestly less effective against the British variant. Fauci told reporters Thursday that it also might be less effective against the South Africa variant.

The South Africa variant (501Y.V2)

Where and when was it discovered?

This mutation, also referred to as B1.351, was found in South Africa in early October and announced in December, when the country’s health minister said the strain seemed to affect young people more than previous strains. This variant may have contributed to a surge of infections and hospitalizations across South Africa.

Where is it?

This mutation has been identified in more than two dozen countries, including Canada, Australia and Israel, but not in the United States.

What makes it different?

This mutation shares some similarities to the U.K. variant and, like that strain, appears to be more transmissible. There is no evidence that it is more lethal. Scott Gottlieb, former director of the Food and Drug Administration, has suggested that this variant might be more resistant to antibody therapies.

Will vaccines work?

The vaccines may have a diminished impact against this variant, but they probably will still be effective, top infectious-diseases expert Anthony S. Fauci said in January. Moderna has said its vaccine protects against the South Africa variant, with an important caveat: The vaccine-elicited antibodies were also less effective at neutralizing this mutation in a laboratory dish.

Ravindra Gupta, a professor of clinical microbiology at the University of Cambridge, found in a study of older adults that the immune response triggered by the Pfizer vaccine was modestly less effective against the British variant. Fauci told reporters Thursday that it also might be less effective against the South Africa variant.

The Denmark variant (L452R)

Where and when was it discovered?

This variant was detected in Denmark in March.

Where is it now?

The mutation has been spreading in Northern California and has been linked to outbreaks at nursing homes, jails and a hospital in the San Jose area. It has also been confirmed in Southern California and more than a dozen other states.

What makes it different?

It’s not yet clear whether this coronavirus strain is any more transmissible or lethal than the dominant mutation.

Will vaccines work?

Some scientists think this variant might be more resistant to vaccines because the mutation is in the spike protein, which enables the virus to attach to cells. But scientists also say that more study is needed before they can draw conclusions.

The original variant (D614G)

Where and when was it discovered?

This mutation, known to scientists simply as “G,” was discovered in China in January 2020. It soon spread through New York City and Europe.

Where is it?

The “G” mutation has become ubiquitous. By July, about 70 percent of the 50,000 genomes of the coronavirus uploaded by researchers worldwide to a shared database carried the variant.

What makes it different?

Some scientists think this mutation is significantly more transmissible than the original strain of the virus. That’s because this variant has four to five times more spikes on its surface. Those spikes enable the virus to latch onto and infect cells. But other scientists still contest the greater transmissibility.

Will vaccines work?

The G variant was the dominant strain when 2020 vaccine trials took place. The Pfizer and Moderna vaccines showed a 95 percent efficacy in trials.

How can we protect ourselves from the variants?

The same protective measures that have warded off the virus throughout the pandemic — maintaining social distance, wearing masks and washing our hands — are even more critical in the face of more transmissible variants. Those guidelines will simultaneously keep you from becoming ill from one of those variants, while making it harder for the virus to mutate in the first place.

“Viruses don’t mutate unless they replicate,” Fauci said in January.

But it’s also important for scientists to learn as much as they can about these variants, in case there are specific ways we can slow their spread. Until the research exists, we can’t make assumptions about what new variants will do.

What do the variants mean for vaccines?

“We need to get as many people vaccinated with the current vaccine that we have as we possibly can … and prepare for the potential eventuality that we might have to update this vaccine sometime in the future.” — Fauci in January

As more significant variants are reported, the obvious (and arguably most important) question is whether the vaccines will work on them. Some of the mutations have sparked particular concern because they affect the spikes on the virus, which is what the vaccines target.

In short, the pharmaceutical companies are testing new variants against their vaccines and spinning up new trials. Moderna and Pfizer-BioNTech can update their vaccines quickly because of their mRNA technology, which can be reprogrammed to target new variants.

Moderna studied how two of the variants, the U.K. and South Africa, respond to its vaccine. It was about the same for the U.K. variant, but they noticed a diminished response for the South Africa variant. The company then launched two new studies to address the variants: One that bumps the two-dose regimen to three and another to test an all-new vaccine specific to the South Africa variant.

A growing number of scientists anticipate that we will eventually need something similar to the annual flu shot — companies will periodically update their vaccines to match the prevalent coronavirus variants, and we will need to get boosters to stay protected.

“With flu, we need to adapt the vaccines. We can see that already,” said Ravindra Gupta, a professor of clinical microbiology at the University of Cambridge. “The companies do realize there is a problem in the longer term, and they will deal with it just as we have done with flu every year.”

Joel Achenbach, William Booth, Carolyn Y. Johnson, Sarah Kaplan and Fenit Nirappil contributed to this report.