California’s ‘Epsilon’ COVID-19 Variant Could Evade Vaccines: Study

July 8, 2021 Updated: July 8, 2021

A variant of the CCP virus has properties that may help it be more resistant to current vaccines or the immunity a person has gained from a past COVID-19 infection, according to a new peer-reviewed study.

The “Epsilon” variant, first detected in California in May 2020, has three mutations in its spike protein that help it to neutralize antibodies that are produced by mRNA vaccines such as Pfizer and Moderna, researchers from the University of Washington and the San Francisco-based lab Vir Biotechnology stated in their report.

Spike proteins are found on the surface of the coronavirus and are what enable the virus to attach to and enter human cells. Current vaccines are being used against it.

The study, published in the journal Science on July 1, suggests that the spike protein mutations may also help the Epsilon variant evade the immunity that a person previously developed from past infection with the CCP virus, which causes the disease COVID-19.

The effectiveness of antibodies generated by current vaccines or by a person’s previous infection was 50 to 70 percent less effective against the Epsilon variant than against wild-type circulating CCP virus strains (that contain no major mutations), according to the study’s findings.

The Epsilon variant has split into two lineages—B.1.427 and B.1.429—since its first emergence. Cases of the variant became more widespread in the United States, and it has since been reported in at least 34 other countries.

As of July 7, the California Department of Public Health has recorded 23,464 Epsilon cases in California. The United States has recorded at least 47,987 cases in total, which make up 97 percent of the 49,221 Epsilon cases worldwide, the Daily Mail reported. The Centers for Disease Control and Prevention (CDC) says the variant currently accounts for 0.1 percent of total CCP virus cases in the United States.

The variant is believed to be about 20 percent more infectious relative to wild-type circulating CCP virus strains, according to the CDC.

The CDC previously labeled Epsilon a “variant of concern,” but its classification was deescalated to “variant of interest” on June 29, which the agency says is due to the “significant decrease” in the proportion of the virus circulating in the country, as well as “available data indicating that vaccines and treatments are effective against this variant.”

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