Viruses constantly change through mutation, and the novel coronavirus is no different. Multiple variants of the virus that causes COVID-19 have been documented globally and in the U.S., reports the CDC.
Here is a snapshot of what we know about the novel coronavirus variants, what questions remain and what their spread could mean for the U.S.:
What we know about the variants. COVID-19 variant B.1.1.7 was initially detected in the U.K. in September and is now highly prevalent in London and southeast England, according to the CDC. The variant appears to spread more easily and quickly than other variants, but there is no current evidence that it causes more severe illness or increases risk of death. The variant has been detected in numerous countries, including the U.S., where more than 50 cases have been confirmed.
Another variant known as 501.V2 has emerged in South Africa. Initially detected in October, the variant shares some mutations with the U.K. strain and also seems to spread more easily and quickly than other variants. There isn't any evidence at this time that the new variant causes more severe illness or increases risk of death. So far, the variant has been detected in Brazil, the U.K., France, Switzerland, Japan, Austria and Zambia.
Another variant emerged in Nigeria, but there's no evidence to indicate the variant is causing more severe illness or increased spread at this time.
"I would say the U.K., South African and Nigerian variants are the ones that are worrisome to our pandemic response," Mariah Gesink, an infection preventionist at CHI Health Lakeside in Omaha, Neb., told Becker's. "Has the virus's virulence or pathogenicity changed? Will the vaccine provide immunity to the new variants? Will our diagnostic tests be able to detect the new variants?"
What the variants may mean for hospitals. COVID-19 infections are steadily rising in the U.K. amid variant B.1.1.7's presence, and hospitalizations are up 40 percent compared to the spring peak, U.K. Prime Minister Boris Johnson said Jan. 4, according to Bloomberg.. Wide-scale, uncontrolled spread of the more infectious U.K. variant in the U.S. could spell out trouble for hospitals nationwide, which are already overburdened by the current COVID-19 surge. As of Jan. 7, the nation reported 132,370 COVID-19 hospitalizations, up from 102,148 a month prior.
What the variants may mean for the nation's vaccination efforts. Pfizer and Moderna are both testing their COVID-19 vaccines against the U.K. variant. Many scientists have said the vaccines will likely hold up against the variant. According to research published Jan. 7 on preprint server bioRxiv, Pfizer and BioNTech's vaccine appears to neutralize the N501Y mutation found in the more infectious U.K. and South Africa variants. The study has not yet been peer-reviewed.
"There's good reason to believe the vaccines will be effective. … Manufacturers are testing them because the vaccine produces immunity in many different ways," Uzma Syed, DO, an infectious disease expert and head of the COVID-19 task force at Long Island, N.Y.-based Good Samaritan Hospital, told CBS News.
The U.K. variant's spread in the U.S. greatly magnifies the need to vaccinate more people more quickly, experts say. As of Jan. 7, the U.S. has distributed 21.4 million vaccine doses nationwide and given 5.9 million people their first shot, far behind the nation's goal of administering 20 million initial doses by the end of 2020.
"We are in a race against time," Dr. Jennifer Nuzzo, an epidemiologist with the Johns Hopkins Center for Health Security in Baltimore, told The Washington Post. "We need to increase our speed in which we act so that we don't allow this virus to spread further and allow this variant to become the dominant one in circulation. The clock is ticking."
What variants may mean for antibody drugs. Coronavirus variants may limit the efficacy of certain treatments, such as monoclonal antibody cocktails that could potentially be eluded by a single mutation, reports The Washington Post.
The South African variant 501.V2 may "obviate" antibody drugs, Scott Gottlieb, MD, former FDA commissioner, told CNBC Jan. 5. The variant may partially avert or weaken existing immunity from a prior COVID-19 infection, according to experimental results recently published in the preprint server bioRxiv and cited by Dr. Gottlieb.
Dr. Shabir Madhi, lead researcher of the Oxford-AstraZeneca vaccine trials in South Africa, told CBS that the country has seen more than 13 coronavirus variants since the start of the pandemic, though 501.V2 is currently the most worrisome. "It's not a given that the vaccine will not work on this variant, but it is a consideration that the vaccine might not have the full efficacy," Dr. Madhi said.
What the variants mean for virus surveillance and response efforts. Without a wide-scale surveillance program to identify and track genetic variations of the coronavirus, U.S. health officials are effectively flying blind when it comes to understanding the new variant's spread and how to contain it. At present, roughly 1.4 million Americans test positive for COVID-19 each week, but researchers are only performing genetic sequencing on fewer than 3,000 samples weekly.
Implementing a national surveillance program for COVID-19 variants would help U.S. health officials understand how widespread the variant is and identify emerging hot spots, scientists told The New York Times.
The U.K. variant's presence in the U.S. also reinforces the need to strictly follow public health measures, according to Anthony Fauci, MD, director of the National Institute of Allergy and Infectious Diseases.
"You always have to be concerned when you see mutations that have a functional capability. We know from the experience in the U.K. that this particular virus is spreading much more rapidly," Dr. Fauci told NPR. "This just underscores the need to adhere to the public health measures that would prevent the spread of any virus, whatever the mutant is."
Could variants cause the country to lock down again? Britain entered its third national lockdown Jan. 4, which will remain in effect until mid-February, according to The Washington Post. The lockdown came after increasingly tighter restrictions failed to control skyrocketing case counts in the country. The U.S. is still trying to understand how far and wide the U.K. variant has spread in the U.S., which could affect how the country responds. That being said, Dr. Fauci said a national lockdown may not be in store for the U.S., especially considering many Americans' COVID-19 fatigue.
"At this point a total country lockdown, I don't think there's any enthusiasm for that," Dr. Fauci told NPR. "I don't think this is something that we're ready for on a countrywide basis. … Short of that, you can do a lot of things. … You may look at selective lockdowns in certain parts of the state. But, you know, you have to keep your eye on everything that's going on and always keep all options open."
What we still don't know about COVID-19 variants. More research is needed to understand the coronavirus variants, specifically regarding how widely variants have spread, how variants differ, and how the disease caused by new variants differs from the disease caused by other variants, reports the CDC.
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