As the coronavirus’ grip begins—tentatively and ploddingly—to loosen after months spent bludgeoning communities with deadly surges of new infections, several new variants of the virus have emerged, perhaps carrying the potential to breathe new life into the pandemic.

Four variants—discovered in Britain, South Africa, Brazil, and California respectively—possess genetic mutations that appear to make them between 30 and 70 percent more infectious than the original virus, preliminary studies indicate. Some may also be capable of evading the defenses the body generates to fight the virus and may lower the efficacy of existing vaccines.

For colleges and universities attempting to walk the tightrope of reopening their campuses without fueling virus outbreaks among their communities, the variants may offer a uniquely serious threat. 

Though their exact significance remains unclear, the variants have already driven outbreaks in a handful of countries, and infectious disease experts are warning they could ignite similar surges in the U.S., if the proper precautions are not followed. California state health officials believe a variant first discovered in the state was largely responsible for two outbreaks in Santa Clara County. 

“It is even more imperative that we take these protective measures,” Dr. Michael Siegel, a professor of community health sciences at Boston University, said in an interview. “If we don’t, the consequences become greater because more people becoming infected means that more people are going to suffer the consequences, and more people are going to die.”

Emerson administrators acknowledged the new variants for the first time on Jan. 25 in a community-wide email. They told students that now, more than ever, strict adherence to the college’s safety protocols—wearing masks, regular COVID-19 testing, and reduced space capacity, among others — is necessary to keep virus transmission rates low. Officials do not appear to be on the path to enforcing any new safety restrictions to respond to the newly emerging variants. 

Infection data from Emerson’s fall semester seems to imply a correlation between cases in the city and cases on campus—college infections ticked up significantly at the end of the term, as cases in Boston shot up. Should the variants drive new surges in the city, the risk of infection at the college may increase.

In a later phone interview, Muurisepp, who serves as the college’s “COVID Lead,” said the variants are cause for concern.

“Certainly it concerns me, and I think that is where it does go back to reinforce all of the protocols we have in place,” he said. “While it does seem to spread easier, maybe faster, we’ve been reassured that the measures in place also can help limit that.” 

As of Jan. 28, each of the four variants of COVID-19 had been found in the U.S.

The science

It’s not a surprise that COVID-19 has mutated. Viruses, by nature, mutate constantly. The particular strain of the coronavirus the world is currently at odds with, SARS-COV-2, has likely already mutated thousands of times. Most mutations are harmless, but sometimes, if enough mutations pile up or occur in a certain part of the virus, they can make significant alterations to its basic nature, Dr. Todd Ellerin, director of infectious diseases at South Shore Hospital in Weymouth, said in an interview.

Some of the variants that have popped up, he said, have a high number of mutations, some of which are found on the virus’ spike protein, which binds the virus to a person’s cells. Those mutations allow the virus to attach to a cell more efficiently, which is why these variants are more transmissible. 

“The thought is that… [the virus can enter] the cell faster, better, more efficiently, more effectively, and it can enter the cell more,” Ellerin said. “That means it can spread more efficiently from person to person, And the amount of virus potentially can be greater. Why is that important? Because we think that most likely, the more virus that someone has, the more contagious they can be.”

B.1.1.7 – the U.K. variant

In mid-December, new coronavirus cases in Britain were on an alarming rise, driven by a new variant—B.1.1.7. That variant, now commonly referred to as the U.K. variant, charged a surge in cases unlike any Britain has seen in its nearly year-long bout with the virus.

At the peak of the surge, the seven-day average of new, daily cases sat at nearly 60,000. The previous high for that metric was around 25,000, which Britain hit in November during a strict national lockdown.

Researchers would soon discover that B.1.1.7 is significantly more infectious than the original virus—preliminary research indicates somewhere between 30 and 70 percent, Ellerin said. 

Britain’s plight may serve as a warning to the U.S. as to how quickly infections of B.1.1.7 may be capable of spiraling out of control. It is perhaps also a dire warning sign to colleges, whose reopenings rely on preventing community spread of the virus. 

Adding to Britain’s dilemma, Prime Minister Boris Johnson indicated for the first time last Friday that B.1.1.7 may too be more deadly than the original virus, though the evidence to bolster his claim is based on mathematical comparisons of death rates associated with the U.K. variant and other versions of the virus.

On Sunday, Dr. Anthony Fauci, the U.S.’ leading infectious disease expert, signaled that he believed the variant could possibly lead to a higher rate of mortality, though he emphasized the preliminary nature of the data.

But regardless of B.1.1.7’s relative mortality rate, what’s clear is that a more-transmissible variant of the virus will intrinsically lead to more death, as it will spread to more people at a faster pace. The more infections of the virus, the more deaths, even at the current estimated mortality rate.

“There’s some preliminary observational evidence that shows that it may be a little bit more deadly,” Ellerin said. “But what we don’t know is—the difference was 10 per 1,000 people versus 13 or 14 per 1,000 people. I’m not saying that’s nothing. That’s real. But the question is, is it the virus itself? Or were we observing at a time when the hospitals were over capacity?”

Researchers have now traced the first occurrence of the B.1.1.7 in the U.K. back to mid-September, when restrictions in Britain were greatly relaxed. 

Britain now appears to have passed the peak of the surge; the seven-day average of new daily infections is down to around 32,000. But the effects of the surge are far from gone. Britain’s hospitals are now overwhelmed; their workers seeing firsthand the deadly ramifications of a consequential variant identified too late. 

In a Jan. 15 projection, the Centers for Disease Control and Prevention warned that the U.K. variant may be the dominant version of the virus in the U.S. by as early as March.

As of publication, B.1.1.7 has been detected in 26 U.S. states, including Massachusetts. 

501Y.V2 – the South African variant

In October, researchers in South Africa identified what was the first case of another COVID-19 variant—this one named 501Y.V2. Three months later, the country was battling its most powerful surge in cases since the pandemic began, driven by the newly discovered variant.

Like B.1.1.7, 501Y.V2 is believed to be significantly more infectious than previous variants of COVID-19. But of all the newly detected strains, the South African variant is perhaps the most worrisome, Ellerin said.

Early research has found that 501Y.V2 may potentially possess the capability to “dodge” COVID-19 antibodies, the proteins a person infected with the virus develops to fight it. That means that those who have already been infected with COVID-19 may be at greater risk of reinfection from 501Y.V2 than other versions of the virus.

Studies from Pfizer-BioNTech and Moderna, the manufacturers of the two COVID-19 vaccines approved for emergency use in the U.S., indicated that their shots are still enough to protect against the virus. But, the vaccines may be less effective against 501Y.V2 than against other versions of COVID-19. The study conducted by Moderna found that, while the vaccine still provided what researchers believe to be enough antibodies to neutralize the virus, it produced fewer than generated against other variants. 

“The concern about this is that it looks like in the lab that this South African variant is resistant to some of the monoclonal antibody therapeutics,” Ellerin said. “The South African variant had a six-fold reduction in the amount of neutralizing antibodies, but what they said is they think that even with a six-fold reduction, it’s still robust enough that it should be okay when it comes to vaccines in real life.”

Moderna has said that, as a precaution, it will begin work on creating another version of its vaccine to serve as a “booster shot” against 501Y.V2.

Two cases of 501Y.V2 were detected in South Carolina on Thursday, the first time health officials have identified the variant in the U.S. The two cases were found in people with no travel history, an indicator that the variant may already be spreading at the community level.

P.1 – the Brazilian variant

In Manaus, Brazil, COVID-19 cases are once again soaring to unimaginable heights. The city, already ravaged once by the virus in April, is in agony once again, with hospitals overwhelmed and deaths piling up. 

Scientists are scrambling to figure out why. In April, such a high percentage of Manaus’ population was infected with earlier versions of the virus, that researchers believed the city had hit the threshold for “herd immunity.”

The theory was that enough people had been infected with the virus, and inherently built up COVID-19 antibodies, that the entire population of the city would be protected against another surge in cases. 

While little research is available, fingers are pointing to a variant of COVID-19 known as P.1 to explain the city’s decimation.

Like B.1.1.7 and 501Y.V2, researchers believe P.1 is much more transmissible than other versions of COVID-19—and Manaus is perhaps an example of just how fast this variant may be able to spread. 

A Jan. 27 study in The Lancet found that P.1 may also have mutations that allow the virus to avoid COVID-19 antibodies. So those previously infected in Manaus may have been at risk of being reinfected with P.1, effectively eliminating the city’s herd immunity.

The first known case of the P.1 variant in the U.S. was detected in Minnesota on Monday. The person infected recently returned to the U.S. from Brazil.

The implications

Much is unclear about the true implications of these new, more-transmissible variants. Research is so preliminary that it is still unknown whether the variants are capable of spreading even when the proper safety precautions, like wearing masks and social distancing, are in place, Ellerin said.

What we do know, however, is that if the precautions are not followed, variants of a more-transmissible nature appear almost certain to take advantage.

“Our behaviors become very important,” Ellerin said. “But it does, knowing that it’s more contagious, make us say, ‘You know what, we really do want to make sure we’re optimizing the infection prevention measures that we know work.’ Masking is important, but making sure you have the best mask or a better mask is probably more important now than it was before.”

Emerson was largely successful at keeping the virus at bay during the fall, with the exception of an uptick in cases near the end of the semester related to spread off-campus. 

In the vast majority of cases where mass spread of the virus did occur at colleges that reopened for in-person instruction, like Boston College, the spread was driven by off-campus gatherings where safety protocols were flouted. 

More transmissible variants would make those gatherings all the riskier, Professor Jamie Lichtenstein, a biologist who was one of three health experts the college recruited over the summer as a consultant on reopening, said. 

“We’re worried about gatherings in people’s homes, not just apartments, and it’s not unique to Boston—it’s really throughout the U.S.,” Liechtenstein said. “The ventilation standards for homes haven’t been based on infection control, they’re based on not having that smelly dish you made in your kitchen hang around too long.”

Now, public health experts are pushing for Americans to shift away from cloth masks and invest in some of higher quality, like surgical masks or N95s. Those masks, they say, are more effective at preventing COVID-19 particles from reaching the wearer. 

“The other change that epidemiologists and scientists and medical professionals are starting to talk about is having people use higher filtration, better-fitting masks,” Lichtenstein said. “The nice thing about this higher-filtration mask is they don’t just protect others, they also protect the wearer.” 

Emerson administrators have not issued new mask guidance, and appear to be doubling down on their charge towards in-person classes, undeterred by the arrival of the variants in the U.S.

“We’re going to be learning about this as we go along and we’ll continue to analyze how we adjust our day to day,” Muurisepp said. “But the other constant is that we are committed to having in-person instruction. That is still our goal for February 1. At this point in time, we’re not straying from that.”