With the world struggling to get the COVID-19 pandemic under control, reports of emerging virus variants are clearly troubling. New strains appear to be significantly more transmissible and slightly more lethal than the original version.
Although the picture keeps changing as data continues to come out, U.S. public health officials and infectious disease experts share what’s currently known about COVID-19 virus variants of concern:
What causes variants in the COVID-19 virus?
The more COVID-19 spreads, the easier it becomes for variants to show up.
“Variants have been emerging through the entire pandemic,” says Angela Rasmussen, a virologist at the Georgetown University Center for Global Health Science and Security. “That’s just because it’s something that happens when a virus mutates — and mutation happens essentially every time a virus replicates.”
Replication occurs when a virus attaches to host cells from the outside, enters by binding to host cell receptors and then uses protein within the host cell to reproduce.
Mutation means that a virus is undergoing genetic changes. Many of these mutations, or changes that occur at random, are not particularly important, while other mutations can actually make it harder for the virus to replicate, Rasmussen notes.
Other mutations may persist but remain innocuous. “They’re not necessarily giving the virus any sort of competitive advantage,” Rasmussen says. But the problem is “the new variants that have emerged do appear to have a competitive advantage in that they make the virus more transmissible. But we’re not sure exactly how they’re more transmissible.”
The bottom line is: “These variants have emerged because there is so much (COVID-19) transmission that the virus is getting a lot of different opportunities to replicate,” Rasmussen says.
Which are the virus variants of concern?
These three variants of the original SARS-CoV-2 virus are deemed as selected variants of concern by the Centers for Disease Control and Prevention:
— B.1.1.7 (U.K. variant). First identified in England, this strain has since been seen in other European nations, Australia and North America — with the first confirmed U.S. case appearing in a Colorado patient in late December. This is now the most widespread of the three variants of concern in the U.S. population. According to a CDC estimate, this variant may become the dominant strain by early spring.
— B.1.351 (South African variant). Originally identified in South Africa, the B.1.351 variant has since been documented in multiple nations worldwide. In late January, the first U.S. case was confirmed in South Carolina.
— P.1 (Brazil variant). First identified in Brazil, this variant is particularly troubling to infectious disease experts. “The P.1 variant in Brazil is the one that’s most alarming to me,” Rasmussen says. “It seems to be causing a huge uptick in cases in a city that’s already been heavily affected — suggesting that people are getting this despite a relatively high level of population immunity.”
The P.1 variant was first detected in Manaus, Brazil, from blood samples collected from patients seeking COVID-19 testing there in mid-December. An “abrupt increase” in the number of COVID-19 hospital admissions in Manaus was described in a Jan. 27 report in The Lancet. During early January 2021, there were 3,431 such admissions, compared with only 552 admissions for the same number of days in early December 2020.
On Jan. 25, the first documented case of the P.1 variant in the U.S. was confirmed by the Minnesota Department of Health.
How many COVID-19 cases caused by these variants have occurred in the U.S. so far?
As of Feb. 4, according to U.S. figures continually updated by the CDC:
— A total 611 cases of COVID-19 caused by the B.1.1.7 variant have been reported among 33 states.
— For the B.1.351 variant, five cases overall have been reported among two states.
— For the P.1 variant, two cases have been reported in a single state.
Florida, California and New York have had the most COVID-19 cases from emerging variants.
Are variants more contagious than the principle COVID-19 strain?
Yes. “These variants seem to spread more easily and quickly than other variants, which may lead to more cases of COVID-19,” according to the CDC website. “An increase in the number of cases will put more strain on health care resources, lead to more hospitalizations and potentially more deaths.”
The variant first seen in the U.K. is about 50% more transmissible than the prevailing strain, according to Dr. David Cennimo, an adult and pediatric infectious disease expert and assistant professor at Rutgers New Jersey Medical School. Transmissibility data on other variants is still being gathered.
Are variants more deadly?
Apparently yes, but not drastically so. “To put it in perspective, for the normal COVID, the mortality rate was (about) 10 out of 1,000 cases,” says Dr. Tom Kenyon, chief health officer for Project HOPE and a former director of the CDC’s Center for Global Health. “With this new variant, it would be more up around 13 or 14 per 1,000. So, it’s a significant increase but we just don’t want the public to panic and feel like now COVID is going to be uniformly fatal. That’s not what (scientists) are saying.”
How do variants affect COVID-19 treatments like monoclonal antibodies?
An intravenous treatment called monoclonal antibodies has been helping patients with severe COVID-19. A monoclonal antibody is a synthetic version of the antibodies produced by a patient who has recovered from coronavirus infection.
Lab studies suggest that the B.1.351 (S. African) variant may severely diminish the virus-neutralizing action of some monoclonal antibodies, according to the CDC summary presented at the media briefing.
How do COVID-19 variants affect vaccine effectiveness?
On Jan. 27, the White House held a media briefing, along with public health officials from agencies including the CDC, which addressed the new variants among other COVID-19 topics. Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, summarized CDC findings:
— The B.1.1.7 (U.K.) variant may slightly diminish antibodies induced by vaccines, laboratory studies suggest.
— The B.1.351 (South African) variant may moderately diminish antibodies induced by vaccines, according to laboratory studies.
— The P.1 (Brazil) variant is still undergoing lab testing with results pending.
How effective are specific vaccines against variants?
Vaccines do provide protection against the new variants, although not quite as much as for the original COVID-19 strain.
Moderna’s vaccine has “reduced but still significant neutralization” against the South African variant, according to a preprint study released Jan. 25. “No significant impact on neutralization” against the U.K variant was seen. The study has not yet undergone peer review and findings should be viewed as preliminary.
The findings mean that “antibodies elicited by the vaccine could still neutralize B.1.351 (South African) virus,” Rasmussen explains. “They were just less effective in doing so than for (the B.1.1.7 and other variants) that have been circulating throughout the pandemic.”
Pfizer’s vaccine is slightly less effective against the South African strain than the original virus, also according to a preliminary industry study.
The Novavax vaccine has 86% efficacy against the U.K. variant, according to a study released Feb. 1 in the BMJ. The same vaccine has 60% efficacy against the South African variant. The vaccine is not yet approved by the Food and Drug Administration for use in the U.S. outside of clinical trials.
Johnson & Johnson announced on Jan. 29 that the J&J-Janssen single-dose vaccine, still in clinical trials, was 66% effective overall against preventing moderate-to-severe COVID-19. In trials done in South Africa, effectiveness was lower at 57%. However, the company reported an 85% effectiveness rate in preventing severe disease, COVID-related hospitalization and death.
What are vaccine makers now doing to address these variants?
Moderna has announced it will begin testing a booster vaccine specifically developed to combat the South African strain.
Pfizer-BioNTech also announced plans to develop booster shots that can protect against contagious COVID-19 variants.
Creating boosters “is a really smart thing to do — it’s being proactive,” Rasmussen says. “The nice thing about these mRNA vaccines is that they’re very easy to change to deal with these variants. But it will, of course, take time to get regulatory approval and to manufacture them so that they will make a difference.”
Are children at higher risk of infection with any variants?
“Right now, in the U.S., we’re not seeing that,” Cennimo says. “There was some signal in England that there were more children being infected than previously, so their numbers went up in children. That has not been borne out in the United States.”
What makes these emerging strains so concerning even as vaccination is ramping up?
“It’s concerning in the short term just because even though case numbers have started to go down here in the U.S., we are in a situation where we don’t want to have them start going back up,” Rasmussen says. “More transmissible means potentially more cases, which means more people in the hospital, which means more people dying and more pressure on the health care system. And this is not a good time to have that happen.”
Could the U.S. have avoided COVID-19 variants through measures like tighter travel restrictions?
“We have to assume these variants are with us,” Kenyon says. “It’s a global pandemic. So it’s really unlikely these variants are going to stay put. They don’t need a plane ticket; they don’t need a passport. They move with the movement of people.”
Rasmussen is troubled by the potential implications if the current spread of COVID-19 cannot be contained. “I am worried that if we can’t get the transmission down, and we’re still having problems vaccinating people, the virus is going to have lots of opportunities to replicate and acquire new mutations on top of the ones that are variants, which could allow them to eventually get around vaccines,” she says. “That’s a long-term concern.”
How can you protect yourself from variants?
“In the short-term, right now, the demand for the vaccine far exceeds the supply, and there are all these distribution issues,” Rasmussen says. “So, being that we can’t immediately get vaccinated, we need to really double down on all those other measures — masks, distancing, avoiding gatherings, avoiding enclosed spaces, ventilating if possible, washing your hands, disinfecting high-touch surfaces.”
Cennimo also emphasizes the importance of continuing to take precautions. “If you’re really worried about the variants, I hope that you’re really worried about getting COVID in general,” he says. Many of his patients “keep banging the drum of anxiety about the variants,” he adds. “I just tell them, to be clear: You really shouldn’t catch regular COVID either.”
More from U.S. News