First Two Cases of South African Variant Identified in California; Detected in Santa Clara and Alameda Counties

February 10, 2021

Public health officials urge continued vigilance to slow the spread of COVID-19 in light of confirmed cases of B.1.351 variant

Santa Clara County, CA – The first cases identified in California of the B.1.351 variant of SARS-CoV-2, also known as the South African variant, have been detected locally, one in Santa Clara County and one in Alameda County.

In the Santa Clara County case, the individual and a household member recently returned from international travel in mid-January and first experienced symptoms several days later. Fortunately, the pair followed Santa Clara County’s 10-day mandatory travel quarantine and were isolated in their apartment for the entire infectious period. The case in Alameda County remains under investigation.

“This is an important example of how public health measures can help break the chain of transmission and why it is critical that we as a community continue to avoid travel and quarantine upon return,” said Dr. Sara Cody, Health Officer and Director of Public Health for the County of Santa Clara.

The two cases were detected as part of genomic sequencing efforts through Stanford University laboratories. Currently, only a fraction of COVID-19 positive cases are sequenced as the County and its partners actively work to ramp up sequencing capacity.

“The cases we share with you today are only the ones that have been confirmed through genomic sequencing. As we work quickly to learn more, our best defense right now is to stay vigilant and reduce transmission as much as possible,” said Dr. Nicholas Moss, Health Officer for the County of Alameda. “The more chances the virus has to spread, the more opportunities it has to adapt and create new variants. This is a warning to all of us that we must stay on top of community transmission.”

Public health officials strongly discourage travel and remind residents to reduce their risk of exposure to anyone they don’t live with. Always wear a mask outside the home, maintain a distance of at least six feet from those outside of the household especially when indoors, and stay home as much as possible except for essential activities. Residents should also stay current on vaccine eligibility in their area, and when their turn comes, get vaccinated as soon as possible.

The Centers for Disease Control and Prevention on Wednesday released data showing that double masking, such as wearing a cloth face covering on top of a surgical mask, is more effective at reducing virus transmission. Residents are encouraged to follow these recommendations on double-masking and making sure face coverings are tight-fitting.

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