By Andrea Nakano

SAN FRANCISCO (KPIX) — Two studies released Monday reveal some alarming findings about a California variant of COVID-19. The strain is showing up in half of the samples in 44 California counties and there are signs that it causes severe disease and spreads quickly.

This mutation has been here since May and one local scientist estimates it is now responsible for roughly half of cases in the state.

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Dr. Charles Chiu has been working in his lab in collaboration with California Department of Public Health to identify how prevalent this variant may be.

Dr. Chiu not the only one. UCSF teamed up with Chan Zuckerberg Biohub, which looked into cases in San Francisco’s Mission District.

“What we discovered in November was that this variant in the community was about 16 percent of positive cases,” said Dr. Joe DiRisi of CZ Biohub. “And then when we sampled during the weeks of January 11th to the 27th, it was fully 53 percent.”

According to UCSF Epidemiologist Dr. George Rutherford, the California variant is one of four major ones circulating in the state.

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“We’re going to keep seeing variants forever from this virus. Viruses mutate, they mutate all the time,” Dr. Rutherford said.

Rutherford said it’s not uncommon for variants to escalate transmission or make vaccines less effective.

“[The] CDC thinks that the UK strain is going to be one the dominant strain by April. Now what does that mean? Largely nothing,” he said.

As scientists keep tabs of the mutations to coronavirus, President Joe Biden’s chief medical advisor Dr. Anthony Fauci appeared on Panetta Institute’s lecture series Monday night. He says the best way to beat this pandemic is with a unified approach.

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Dr. Fauci said, “As we move forward, we have to realize that it’s not over yet. An overwhelming majority has to be vaccinated, especially with these variants or else we will always be vulnerable.”