Bay Area COVID-19 Testing Initiative to Assess Impact, Guide Safe Reopening of California Economy

$13.6 Million Commitment from Chan Zuckerberg Initiative Funds UCSF, Stanford, CZ Biohub Research to Track New Infections, Better Understand Population-Level Immunity

COVID testing kits

A new large-scale, long-term research collaboration between UC San Francisco, Stanford University, and the Chan Zuckerberg Biohub (CZ Biohub), supported by a $13.6 million commitment from the Chan Zuckerberg Initiative (CZI), aims to better understand the spread of COVID-19 across the San Francisco Bay Area.

Beginning in early May, and over the next nine months, the consortium, which is led by principal investigators George W. Rutherford, MD, from UCSF, and Stanford’s Yvonne A. Maldonado, MD, will support two long-term studies.

The first, conducted by Rutherford and Maldonado, will sample a broad, representative population in the Bay Area to provide data crucial for informing policy decisions about how to safely reopen California’s economy and to make sure transmission remains low while we await a vaccine. The second, focused on Bay Area health care workers, will examine whether COVID-19 antibodies protect individuals against reinfection, and if so, for how long. This information could be critical to protecting frontline health care workers in California and around the globe.

“To reopen society in the Bay Area and keep health care workers safe, we need to first understand the epidemiology of this disease,” said CZI co-founder and co-CEO Priscilla Chan, MD. “How much of our population is currently infected with COVID-19? How prevalent is asymptomatic spread? And how can we use this information to better understand who may still be at risk in the future? There is no shortcut to answering these questions – it will require testing, retesting, and the sort of rigorous public health surveying this program is focused on in California. We’re grateful to help accelerate this work and partner with Stanford and UCSF – two of our state’s and the world’s greatest scientific research institutions – to help find these answers.”

California Health and Human Services Agency Secretary Mark Ghaly, MD, MPH, said, “One of the critical steps for California to begin gradually reopening our economy is wrapping our arms around community surveillance, so that we continue to be guided by science. We are grateful to the Chan Zuckerberg Initiative, the Chan Zuckerberg Biohub, UCSF and Stanford University for adding to this critical body of data.”

Consortium of Bay Area Residents

In the first study, the consortium will contact Bay Area residents by letter, with follow-up phone calls, to recruit a representative sample of roughly 4,000 individuals. To enroll in this study, participants must have previously tested negative for COVID-19 and be following state-required shelter-in-place guidelines now in place in Alameda, Contra Costa, Marin, San Francisco, San Mateo and Santa Clara counties.

Members of the study cohort will be tested once per month through December 2020 using both polymerase chain reaction (PCR) diagnostic testing to determine the rate of new infections, as well as serological (“antibody”) testing to understand if participants had unknowingly been infected but recovered over the course of a given month. The viral genomes from all positive samples will be sequenced by researchers at CZ Biohub in order to identify local transmission chains or introductions of virus from outside the Bay Area, in addition to shedding light on whether co-infections with other pathogens play a significant role in COVID-19. Altogether, the combined data will provide critical insights into the changing rates of COVID-19 infections as the Bay Area begins to return to work.

Thousands of Health Care Workers

In a second study – conducted by infectious disease specialists Sarah Doernberg, MD, of UCSF Health, Marisa Holubar, MD, of Stanford Medicine, and Vivek Jain, MD, MAS, of Zuckerberg San Francisco General Hospital – the consortium will examine the impact of COVID-19 on health care systems and their workforce.

Researchers will recruit a cohort of roughly 3,500 Bay Area health care workers who previously tested negative for COVID-19 and retest them weekly for at least 12 weeks using PCR and serological testing. The goal is to determine the rate at which healthcare workers acquire COVID-19 with or without symptoms. Health care workers found to be seropositive on recruitment will be followed in parallel through December 2020 to better understand their immunity and likelihood of reinfection. There are currently significant knowledge gaps regarding the nature of immunity to COVID-19, and this study will help surface critical insights to better protect frontline healthcare workers.

“Though we are still in the midst of responding to the first phases of this pandemic, we must also look to the future,” said UCSF Chancellor Sam Hawgood, MBBS. “By assembling reliable data on COVID-19 prevalence and exposure in our region, we can help protect our Bay Area health care workforce and better determine when and how we can safely begin to reopen our state’s economy. Through this new partnership with the Chan Zuckerberg Initiative, CZ Biohub, and our colleagues at Stanford, we will build a foundation for science-based policies that can guide California and the nation in the challenging months ahead.”

Stanford President Marc Tessier-Lavigne, PhD, said, “The knowledge we gain from these studies will be crucial to understanding the effects of COVID-19 on our region and protecting health care workers here and around the world. It’s inspiring to see researchers engaging in the kind of robust collaboration we will need to better understand and manage this crisis. We are proud to work with UCSF and the Chan Zuckerberg Initiative, who are outstanding partners in advancing biomedical research to solve the world’s toughest challenges.”

UCSF’s Rutherford, professor of epidemiology, preventive medicine and pediatrics, said, “The data produced by this study will be not only instrumental in deciding when and how to relax our stringent public health interventions but also to monitor the population for new transmissions going forward. These data will be crucial to informing rational public health practice.”

Maldonado, professor of pediatrics and of health research and policy at Stanford Medicine, said, “As California begins to move to a new normal, we need responsible, thoughtful and scientifically sound action to continue protecting our citizens. We are eager to partner with our colleagues at UCSF and the Chan Zuckerberg Initiative to learn whether and how the virus spreads in the coming months and if previous infection confers lasting immunity. This knowledge will be critical in coming months as we explore new treatment and prevention options for the novel coronavirus.”

About UCSF: The University of California, San Francisco (UCSF) is exclusively focused on the health sciences and is dedicated to promoting health worldwide through advanced biomedical research, graduate-level education in the life sciences and health professions, and excellence in patient care. UCSF Health, which serves as UCSF’s primary academic medical center, includes top-ranked specialty hospitals and other clinical programs, and has affiliations throughout the Bay Area.

About Stanford University: With basic sciences, medicine and two hospitals housed on a single campus, Stanford is positioned to accelerate solutions for humanity’s greatest health challenges. Stanford’s culture of collaboration draws researchers together around common problems, and a spirit of innovation allows for translation of discoveries into proven solutions. Learn more at

About the Chan Zuckerberg Biohub: The Chan Zuckerberg Biohub is a nonprofit research organization setting the standard for collaborative science, where leaders in science and technology come together to drive discovery and support the bold vision to cure, prevent or manage disease in our children’s lifetime. The CZ Biohub seeks to understand the fundamental mechanisms underlying disease and to develop new technologies that will lead to actionable diagnostics and effective therapies. The CZ Biohub is a regional research endeavor with international reach, where the Bay Area’s leading institutions – the University of California, Berkeley, Stanford University and the University of California, San Francisco – join forces with the CZ Biohub’s innovative internal team to catalyze impact, benefitting people and partnerships around the world. To learn more, visit

About the Chan Zuckerberg Initiative: Founded by Dr. Priscilla Chan and Mark Zuckerberg in 2015, the Chan Zuckerberg Initiative (CZI) is a new kind of philanthropy that’s leveraging technology to help solve some of the world’s toughest challenges—from eradicating disease, to improving education, to reforming the criminal justice system. Across three core Initiative focus areas of Science, Education, and Justice & Opportunity, we’re pairing engineering with grant-making, impact investing, and policy and advocacy work to help build an inclusive, just and healthy future for everyone. For more information, please visit