Dianna Ng, Gregory Goldgof, Brian Shy, Andrew Levine, Joanna Balcerek, Sagar P Bapat, John Prostko, Mary Rodgers, Kelly Coller, Sandra Pearce, Sergej Franz, Li Du, Mars Stone, Satish Pillai, Alicia Sotomayor-Gonzalez, Venice Servellita, Claudia Sanchez-San Martin, Andrea Granados, Dustin R Glasner, Lucy M Han, Kent Truong, Naomi Akagi, David N Nguyen, Neil Neumann, Daniel Qazi, Elaine Hsu, Wei Gu, Yale A Santos, Brian Custer, Valerie Green, Phillip Williamson, Nancy K Hills, Chuanyi M Lu, Jeffrey D. Whitman, Susan Stramer, Candace Wang, Kevin Reyes, Jill Hakim, Kirk Sujishi, Fariba Alazzeh, Lori Pharm, Ching-Ying Oon, Steve Miller, Theodore Kurtz, John Hackett Jr., Graham Simmons, Michael P Busch, Charles Y Chiu
We report very low SARS-CoV-2 seroprevalence in two San Francisco Bay Area populations. Seropositivity was 0.26% in 387 hospitalized patients admitted for non-respiratory indications and 0.1% in 1,000 blood donors. We additionally describe the longitudinal dynamics of immunoglobulin-G, immunoglobulin-M, and in vitro neutralizing antibody titers in COVID-19 patients. Neutralizing antibodies rise in tandem with immunoglobulin levels following symptom onset, exhibiting median time to seroconversion within one day of each other, and there is >93% positive percent agreement between detection of immunoglobulin-G and neutralizing titers.