LOS ANGELES - As the novel coronavirus continues to claim the lives of Americans and people across the world, multiple coronavirus variants are now circulating around the globe, triggering alarm among scientists and health officials.
Some of the primary of the variants emerged in the fall of 2020, complicating global efforts to combat the coronavirus and contributing to rapid spread in major metropolitan areas, including London and Los Angeles.
There are many varied coronavirus strains circulating around the world, but health experts are primarily concerned with the emergence of three.
As a virus infects people, it can mutate as it makes copies of itself. Some mutations can be harmful to a virus, causing it to die out. Others can offer an advantage and help it spread.
"Not every mutation is created equal," said Mary Petrone, who studies infectious diseases at Yale University. "The virus is going to get lucky now and again."
Monitoring variants is important because of the possibility that they could make vaccines and treatments less effective, or change the way they infect people.
A mutation early in the pandemic fueled the spread of the virus around the world, but there had been no notable changes since — until recently, said Ohio State University biologist Daniel Jones.
Variants first detected in the U.K., South Africa and in Brazil also appear more contagious, experts say.
The UK variant (Known as 20I/501Y.V1, VOC 202012/01, or B.1.1.7)
In the United Kingdom, a variant of SARS-CoV-2 emerged with an unusually large number of mutations.
The variant has since been detected and reported in numerous countries, including the U.S. and Canada, with cases reported in states like California, Colorado and Florida. Most recently, the strain was identified in a man in New York with no recent travel history, suggesting his case was likely from community spread.
"In the United States, 308 cases of B.1.1.7 variant that originated from the U.K. have been confirmed in 26 states as of January 26th," CDC Director Rochelle Walensky said Wednesday during a White House COVID-19 press briefing.
The variant might become dominant in the U.S. by March, according to the U.S. Centers for Disease Control and Prevention.
A recent study suggested that the U.K. variant is more transmissible than the original strain of the coronavirus — and the research suggests it’s affecting a greater proportion of young people.
The study, published Dec. 31 in a pre-print by a team from Imperial College London and elsewhere, found that the variant B.1.1.7 is growing rapidly throughout England, where it was first detected in September.
"These analyses, which have informed U.K. government planning in recent weeks, show that the new variant of concern, B.1.1.7, has substantially higher transmissibility than previous SARS-CoV-2 viruses circulating in the U.K.," said study author Prof. Neil Ferguson of Imperial College London.
"This will make control more difficult and further accentuates the urgency of rolling out vaccination as quickly as possible," Ferguson added.
Researchers also found that individuals under the age of 20 make up a higher percentage of B.1.1.7 cases, identified in the study as the "Variant of Concern (VOC)." But study authors said it remains too soon to determine the "mechanism behind this change," noting that it could have been partly influenced by "the variants spread coinciding with a period where lockdown was in force but schools were open."
The study has not yet been peer-reviewed, and its authors said further research is needed.
A new national lockdown was issued this week for England until at least mid-February in an effort to combat the fast-spreading variant.
Last week, U.K. Prime Minister Boris Johnson announced that the variant has shown evidence of being potentially more deadly.
"Since the beginning of this pandemic, we’ve tried to update you as soon as possible about changes in the scientific data or the analysis," Johnson said. "So I must tell you this afternoon that we’ve been informed today that in addition to spreading more quickly, it also now appears that there is some evidence that the new variant, the variant that was first identified in London and the southeast, may be associated with a higher degree of mortality."
Johnson said that both vaccines that are currently being administered throughout the U.K., Oxford-AstraZeneca and Pfizer, are still effective against the new variant.
Data so far suggests current vaccines should still protect against these variants, though there’s some concern their effectiveness may be slightly diminished. There is some evidence that some antibody treatments may be less effective against certain variants.
The South Africa variant (known as 20H/501Y.V2 or B.1.351)
In South Africa, another variant emerged independently of B.1.1.7.
On Dec. 18, South Africa announced the detection of the mutation in three provinces: Eastern Cape, Western Cape and KwaZulu-Natal provinces.
According to the CDC, the South Africa variant shares some mutations with B.1.1.7, the U.K variant.
The South Africa variant was located in the United States for the first time on Thursday, with two cases diagnosed in South Carolina, accord to the state’s health officials.
Currently, the two cases do not appear to be connected, and the individuals do not have a history of recent travel, the South Carolina Department of Health and Environmental Control said.
"That’s frightening," because it means there could be more undetected cases within the state, Dr. Krutika Kuppalli, an infectious diseases physician at the Medical University of South Carolina in Charleston, told the Associated Press. "It's probably more widespread."
Vaccine company Moderna announced Monday that its current COVID-19 vaccine appears to work against two highly-transmissible coronavirus variants first detected in the U.K. and South Africa. But researchers found that the vaccine may be less effective against the variant discovered in South Africa.
As a precaution, Moderna is developing a new form of the vaccine against the variant that could be used as a booster against the virus.
The Brazil variant (known as P.1)
In Brazil, a variant of SARS-CoV-2 (known as P.1) emerged and was identified in four travelers from Brazil, who were tested during routine screening at Haneda airport outside Tokyo, Japan.
According to the CDC, the Brazil variant has "17 unique mutations, including three in the receptor binding domain of the spike protein."
The variant was also discovered in a Minnesota patient — the first known case documented in the U.S. — officials said.
The Minnesota Department of Health said the variant, known as Brazil P.1 variant, was found in a person who had recently traveled to Brazil.
Officials say the person is a resident of the Twin Cities metro area. They first became sick in early January and were tested on Jan. 9. After their initial positive test, MDH officials told the person to isolate.
The Brazil variant is thought to be more easily spread than the original COVID-19 strain, but it is not yet known if it causes more severe illness.
In a recent study focusing on Manaus, the largest city in the Amazon region in northern Brazil, several new mutations of the COVID-19 virus were discovered in samples taken between Dec. 15-23.
"These findings indicate local transmission and possibly recent increase in the frequency of a new lineage from the Amazon region," study authors wrote.
Researchers explained that the new variant was identified circulating throughout Brazil and had been detected in a case of reinfection in Salvador, a city over 3,000 miles south of Manaus.
The identification of the new and highly-transmissible variant of the deadly coronavirus in Manaus was also the subject of a separate study published in Science Magazine.
Manaus was particularly hard-hit by the virus and "experienced one of the world’s most rapidly growing COVID-19 epidemics, with the Amazon being the worst-hit region," according to the study.
"Our data show that more than 70% of the population has been infected in Manaus approximately seven months after the virus first arrived in the city. This is above the theoretical herd immunity threshold," study authors wrote.
UK/B.1.1.7 lineage (Known as 20I/501Y.V1 Variant of Concern (VOC) 202012/01)
According to the CDC, this variant is estimated to have first emerged in the United Kingdom during September 2020.
The variant "has a mutation in the receptor binding domain (RBD) of the spike protein at position 501, where amino acid asparagine (N) has been replaced with tyrosine (Y)," the CDC wrote.
Since Dec. 20, 2020, several countries have reported cases of the B.1.1.7 lineage, including the United States and Canada.
This variant is associated with increased transmissibility, but there is currently no evidence to suggest that the variant has any impact of the severity of disease of vaccine efficacy.
South Africa/B.1.351 lineage (a.k.a. 20H/501Y.V2)
This variant was first identified in Nelson Mandela Bay, South Africa, in samples beginning in October 2020, and cases have since been detected outside of South Africa.
In addition, the variant also was identified in Zambia in late December 2020, "at which time it appeared to be the predominant variant in the country," the CDC reported.
Currently there is no evidence to suggest that this variant has any impact on disease severity.
Brazil/P.1 lineage (a.k.a. 20J/501Y.V3)
The P.1 emerging variant is a branch off the B.1.1.28 lineage that was first reported in Japan in the travelers from Brazil.
According to the CDC, this variant P.1 lineage contains 17 unique amino acid changes and three deletions.
"There is evidence to suggest that some of the mutations in the P.1 variant may affect its transmissibility and antigenic profile, which may affect the ability of antibodies generated through a previous natural infection or through vaccination to recognize and neutralize the virus," the CDC wrote.
This variant has not yet been identified in the United States.
Catherine Park, Kelly Hayes and the Associated Press contributed to this story.