Bay Briefing: Bay Area sees first confirmed cases of variant that reduces effectiveness of some vaccines FacebookTwitterEmail Lab technician Jason Tran processes COVID-19 test samples at UCSF Microbiology Laboratory in San Francisco.Scott Strazzante / The Chronicle Good morning, Bay Area. It’s Thursday, Feb. 11, and a friendly rivalry is pushing forward the world of competitive surfing. Here’s what you need to know to start your day. ‘A very limited picture’ Two cases of a coronavirus variant first found in South Africa that reduces the effectiveness of some vaccines have been identified in the Bay Area, in Alameda and Santa Clara counties, Gov. Gavin Newsom said Wednesday.