The coronavirus variant, first seen in Los Angeles in July, now accounts for about 44% of new infections in Southern California and more than a third of new infections nationwide, researchers reported Thursday.
In addition, the variant has spread across the United States and to six countries around the world, according to the study in the Journal of the American Medical Assn.
A team from Cedars-Sinai Medical Center in Los Angeles acknowledged that the genetic changes that characterize the fast-moving variant have been passed on from person to person or that they are getting sicker. JAMA report. But the rapid spread of the virus in California is worrying, they wrote.
The homemade variant is different from other versions of the virus found in the USA, including the B.1.1.7 strain from the United Kingdom and the B.1.351 strain from South Africa. But like these new strains, this variant is defined by several mutations in the vein protein of the virus, the ‘coupling mechanism’ that the virus uses to attach to human cells.
One of the five mutations of the California variant, known to scientists as L452R, can alter a particularly critical part of the peak protein called the receptor binding domain.
A study conducted by Howard University researchers last year found that the mutation helps attach the virus more firmly to human cells. It can therefore improve the transmission of the virus.
Both Cedars-Sinai and the UC San Francisco Medical Center are testing samples of the new variant in an effort to determine if the altered genetic makeup has given the virus new powers to spread or gain.
“New variants do not always affect the behavior of a virus in the body,” says Dr. Eric Vail, one of the senior authors of the study.
But because this one has risen amid an ominous surge of new infections in Southern California, and because three of the five changes to the genetic code involve the spike protein, it is of particular importance, says Vail, a molecular pathologist in Cedars- Sinai’s Division of Pathology and Laboratory Medicine.
The rapidly increasing proportion of cases in California is also ominous, the authors said.
Although the variant was barely observable in early October, it accounted for 24% of approximately 4,500 viral specimens collected in the last weeks of 2020 throughout Southern California, and 18% of the specimens nationwide. Less than a month later, the number of new infections increased.
From January 1 to January 22, the variant was responsible for 44% of the coronavirus samples collected in Southern California and 35% of samples from across the state.
In assessing the likely impact of emerging variants elsewhere, scientists have viewed trends such as these as evidence that a new genetic variant has gained a competitive advantage over others already in circulation. One statement would be an increase in portability.
‘If you look at the numbers, they suggest it [the California variant] is probably more contagious, ”said Jasmine Plummer, a Cedars-Sinai researcher who led the study with Vail. But because other factors have contributed to its growing presence, “we need to do more studies” to confirm the suspicion, she warned.
Shaolei Teng, a biologist at Howard University, who led a team to investigate the effect of the virus’ genetic changes, said the variant’s L452R mutation clearly showed its ability to bind to human cells. improve. The change probably also makes it easier for the virus to enter cells, an important step in the replication process.
The mutation is “beneficial to the virus, and could be the reason it has become dominant in California,” Teng said.
What’s more, the variant has started to travel widely. It has been found in Alaska, Arizona, Connecticut, Georgia, Hawaii, Maryland, Michigan, New Mexico, Nevada, New York, Oregon, Rhode Island, South Carolina, Texas, Utah, Washington, Wisconsin, Wyoming and Washington, DC.
It has also migrated to Australia, Denmark, Israel, New Zealand, Singapore and the United Kingdom.
“The emergence of these and other new variants is likely to be a common occurrence until the spread of this virus is reduced,” a team from the National Institute of Allergy and Infectious Diseases wrote in an editorial accompanying the study. “It emphasizes the importance of a global approach to vaccine surveillance, detection and deployment.”
Plummer said travelers from Southern California probably took the new variant with them to other states and states.
According to the U.S. Department of Transportation, Los Angeles International Airport has long been one of the busiest travel destinations in the United States. It is a major U.S. gateway to a number of foreign destinations, including Australia and New Zealand.
While air traffic across the U.S. declined during the pandemic, more than 4 million local and international passengers continued to travel through LAX in November and December, according to Los Angeles World Airports, which operates the airport.