benjamin pinsky says they're also looking for new mutations.them for these very important considerations, whether they're more transmissible, whether they produce more severe disease, and whether there is any impact on the efficacy of that theme. >> reporter: information public health officials will need as they continue to navigate the pandemic. jean elle, nbc bay area news. >> so where it is california stands in terms of vaccine distribution? well, the answer is frustrating. it turns out we're last in the entire country. the state has used only 37% of the vaccines we were given. that means the bulk of the vials are still in freezers throughout the state. >>> now san francisco launched its first mass vaccination site today in the parking lot of city college. 500 people got their first dose of the moderna vaccine, but what people didn't get is an appointment for that necessary second shot. the city's health leaders say that san francisco's supply of vaccine is too inconsistent to promise that second dose on time. >> i'm not overly concerned, no

benjamin pinsky is where scientists have developed new tests to track viral variants and to quickly identify new mutations, information that is critical to understanding if they'll spread more easily. >> the u.k. variant is in over 60 countries now. the south african variant is in over 20 countries. so despite limitations on travel. >> reporter: one strain that is already concerning is known as l-452 r which has been identified as the cause of several outbreaks throughout the region including the deadly christmas day outbreak at kaiser san jose which infected at least 90 people. researchers have already screened hundreds of samples collected through the testing sites and are planning to ramp up over the next week. >> there is plenty that we as individuals can do even if we're not vaccinated to prevent transmission. and we know those methods. >> reporter: surveillance will help determine whether they cause more significant disease or render vaccines less effective. crucial details that could help public health efforts across the country. >> the key is the masking and social distancing and all

benjamin pinsky is tracking this data. >> uk variant, i believe, is in over 60 countries now. the south african variant is in over 20 countries. so, despite limitations on travel. >> reporter: stanford's doctor blish is part of a group of infectious disease researchers who studies this virus as it mutates. >> an emergency call tomorrow to study these variants. >> reporter: the best way to prevent the virus and the variant of covid to spread is to vaccinate as many people as possible fast. >> it is quite reasonable to infer that we could see a surge. >> reporter: in san francisco, luz pena, abcnews. >>> city college of san francisco where 500 people received their shots. but the city finds itself facing the same problem many other communities are dealing with, a shortage of doses. california's promising to deliver another 10,000 next week. that is the number of people mayor london breed wants to vaccinate every day. the priority list could be changing with age moving past some of the essential sectors. >> our schools are still closed and we need to prioritize our educators and

i spoke to dr benjamin pinsky of stanford medicine. he says his test has already confirmed different strains of the virus are in the bay area, including one linked to an outbreak earlier this year in santa clara county and a kaiser san jose. it breaks down samples of the virus he's collected and looks at its genetic sequence, then within 2 to 3 days, scientists can determine whether that covid strain is a variant of some kind. dr. pinsky tells me a diagnostic tool locally keeps everyone informed and prepared. it's important to know about these variants and understand their trance, whether they're more transmissible, which at least some of them appeared to be whether they impact the severity of illness that has not been demonstrated yet. um and then also whether they will impact both the ability of these variants to be. um, neutralized. by antibodies. earlier this week, the nation's top infectious disease doctor anthony fauci says health experts are keeping their eyes on a variant in south africa. doctor fauci called it more dangerous,