Serologic testing for SARS-CoV-2 immunity
Upon publication of the SARS-CoV-2 genome, an assay was designed, validated and deployed at Stanford to detect SARS-CoV-2 in individuals who are actively infected; this molecular test is now being used to screen patients at Stanford and many hospitals in the bay area and beyond.
A critical next step is to develop serologic testing to identify patients with past exposure and possible immunity to SARS-CoV-2 following recovery from an infection. Based on data released from colleagues in China, 8 to 11 days after onset of symptoms blood from infected individuals contains detectable quantities of antibodies to SARS-CoV-2 antigens. These antibodies persist in the blood long after the virus has been cleared, providing a stamp to measure who in the population has been infected, even if they did not show symptoms or did not have molecular testing.
Prior to widespread availability of an effective vaccine, serologic testing for SARS-CoV-2 will be our best tool to:
- Treat critically ill patients by identifying donors of immune plasma
- Optimize allocation of likely limited medicines to those who lack immunity
- Preserve the health care workforce by identifying who can safely interact with patients
- Suppress the spread of disease by identifying those who safely can return to jobs that interact with the public like food service, retail, government, travel, etc.
- Determine “herd immunity”, meaning when enough of the population has become infected that it is safe to discontinue social distancing and shelter-in-place
To address this critical need, we have organized a dream team of Stanford colleagues across diverse areas of science, engineering, and medicine to jointly develop a serologic test for SARS-CoV-2 antibodies. Our goal is to begin to deploy this test into the clinic in the coming weeks, and continue to innovate on more sensitive and selective testing methods. Our goal is to also support the scaling of critical reagents and materials so that we can test hundreds of thousands of patients in the Bay Area over the course of the pandemic and beyond.
Aren’t there commercial tests available?
- Despite our pioneering work in molecular testing for SARS-CoV-2, we have been severely limited in testing at scale because of the scarcity of commercially available reagents. Hence, our resolve to develop a self-sustainable serologic test at Stanford.
- Many serologic tests for SARS-CoV-2 antibodies are now appearing on the market with no information on reproducibility, reliability, or test performance. Very shortly, the world will need a reference platform to which we can compare the likely hundreds of serologic tests that will be offered. Stanford can be this world standard.
- We need to mobilize our efforts now to complete these tasks in the next few weeks in order to make an impact on the pandemic.
Scott Boyd, Tom Montine, Peter Kim, James L Zehnder, Theodore Jardetsky, Benjamin Pinksy, Tho Pham, Chaitan Khosla, Bali Pulendran, Run Shi, Jennifer Cochran, Dana Andersen, Luke Pennington, Taia Wang, Abby Powell, Katharina Roeltgen