California scientists are increasingly concerned about the “home grown” coronavirus variant in the state, with studies showing that the variant is more transmissible than previous strains and may be more resistant to current vaccines, according to press reports .
The variant, known as B.1.427 / B.1.429, first appeared in California last spring, but it didn’t appear on scientists’ radar until this winter, when cases of the variant took off quickly in the state, according to The New York Times. However, scientists were unsure whether the variant was actually more contagious than previous strains or whether it became more common simply by chance – for example, through some over-spreading events.
In a new study, which has not yet been published in a peer-reviewed journal, the researchers analyzed 2,172 virus samples collected in California between September 2020 and January 2021. They found that, although the variant had not yet appeared in September, in January, it became the predominant variant in California, with cases doubling every 18 days, The New York Times reported.
What’s more, laboratory studies found that the variant was 40% better at infecting human cells compared to previous strains, according to The New York Times. In addition, people who tested positive for the California variant had twice as much viral load (or levels of the virus) in their nose and throat as people infected with other versions of the virus. This may mean that people infected with the California variant can spread more easily than people infected with other strains, according to the Los Angeles Times.
The researchers said their findings mean that B.1.427 / B.1.429 should be considered a “concern variant” similar to the variants that emerged in the United Kingdom, South Africa and Brazil.
“The devil is already here,” the study’s lead author, Dr. Charles Chiu, a virologist at the University of California, San Francisco, told the LA Times. “I wish it were different. But science is science.”
Laboratory experiments also found that antibodies in people who had been infected with other strains of the new coronavirus or who had been vaccinated against COVID-19, they were less effective in “neutralizing” or disabling the California variant.
Still, the California variant may not be as successful as the South African variant in escaping current vaccines. In laboratory studies, the South African variant induced levels six times lower than the levels produced in response to other strains, Live Science previously reported. But the levels of antibodies produced in response to the California variant were only twice as low, reported the LA Times.
There is also early evidence that the California variant may be more deadly than other strains. When Chiu and colleagues analyzed about 300 cases of B.1.427 / B.1.429 in San Francisco, they found that those infected with this variant were much more likely to die than those infected with other strains of coronavirus. But, due to the small sample size (only 12 people died in total), the results may not be statistically significant.
Some researchers who were not involved in the new study said the California variant did not appear to pose as much of a threat as other coronavirus variants. “It’s not as important as the others,” William Hanage, an epidemiologist at the Harvard TH Chan School of Public Health in Boston, told The New York Times. He noted that the California variant did not appear to take off in other parts of the country or the world, while B.1.1.7 (the United Kingdom variant) appears to take over quickly wherever it is introduced.
A study released earlier this month estimated that B.1.1.7 is up to 45% more transmissible than previous strains in the USA, according to CNN. Previous California data suggests that B.1.427 / B.1.429 may be up to 24% more transmissible than previous strains, the Los Angeles Times reported.
Studies in the coming weeks will provide a better understanding of how big problem B.1.427 / B.1.429 represents and whether it will beat other variants of the coronavirus that have already emerged in the state, including the UK and South African variant, reported the New York Times.
Originally published on Live Science.