Two strains of coronavirus that emerged in California last summer and fall have been declared ‘variants of concern’ by the Centers for Disease Control and Prevention (CDC).
Health officials think that each variant is about 20 percent more transmissible than the currently dominant ‘original’ variant, based on early data.
Lab studies also suggest that some antibody treatments may not work s well against the two variants.
In particular, one of two antibody drugs by Eli Lilly will no longer be shipped to California, Arizona or Nevada by the Department of Health and Human Services (HHS) because the variants are so prevalent in the two states that treatments may not be worthwhile there.
Infection-blocking antibodies triggered by vaccines don’t work quite as well against the two variants, but so far the new strains don’t appear to weaken the effects of these immune cells enough to stop shots from being protective.
With the addition of the California strains – which have been identified in almost every state – there are now five variants of concern (VOC) spreading in the US, including those from South Africa Brazil and the UK.
However, none of these mutants has ruisen to the level of a ‘variant of high consequence,’ the most dangerous designation made by the CDC.
CDC declared two coronavirus strains that emerged in California – B1429 (pictured) and B1427 – ‘variants of concern’ because they are more transmissible. B1429 has now been found in every state except South Dakota
B1427 has been detected in all US states except South Dakota, West Virginia, Vermont and Alaska (pictured)
Still, the California variants have proven very capable of spreading quickly.
The strain that was found first (in July, according to Outbreak.info), carries four mutations.
The slightly younger variant, which emerged in September, carries two of those four mutations.
Due to their similarities and they’re emergency around the same time in Southern California, the two variants are often referred to collectively as CAL2oC.
Together, they accounted for more than half of all coronavirus cases in the state by February, according to estimates based on viral genome sequencing done by the University of California, San Francisco.
The authors of the study suggested that the variant pair could be responsible for 90 percent of California’s cases by the end of this month.
As it stands, 25 percent of all samples tested for mutations in California have been positive for the B1429, according to tracking from Outbreak.info.
In the latest batch of samples submitted to international databases, the variant accounts for 52 percent of cases in California.
As of March 9, it accounted for nine percent of US samples, but was not detected in any of the latest set (which Outbreak.info notes was small, and likely not representative of what’s really circulating in the nation.
Over the entire course of the pandemic, the variant has been found in seven percent of US samples.
The slightly younger B1427 variant has been detected in three percent of samples submitted cumulatively.
It was flagged found in 18 percent of samples from California submitted on March 5.
B1427 has been detected in all US states except South Dakota, West Virginia, Vermont and Alaska.
Already, it accounts for eight percent of samples submitted from Nevada.
The more mutated B1429 variant is now in every single state except South Dakota and, according to Outbreak.info, it is even more prevalent in Nevada (24 percent) than in California (20 percent).
Each has a mutation that makes it better at latching onto human cells, which makes it more easily transmissible.
And antibody drugs that use just one type of antibody to treat infection, rather than two, may be less effective, early lab tests suggest.
The HHS has paused shipments of Eli Lilly’s monoclonal antibody – meaning the drug contains just one lab-designed type of antibody – to California, Arizona and Nevada.
Food and Drug Administration (FDA) regulators also updated the stipulations of the emergency use authorization – a form of temporary approval with a lower bar than full approval – for both of Eli Lilly’s antibody drugs and the one made by Regeneron to require the companies to ‘monitor’ variants that could weaken their treatments.
As of yet there is no requirement for them to change the formulations of their the drugs, but there could be if the drugs are rendered ineffective by variants.
So far, it appears that Eli Lilly’s other treatment, a combination of bamlanivimab and etesevimab still works against the California variant, as does Regeneron’s drug. Both treatments rae antibody ‘cocktails.’