Background The first US case of SARS-CoV-2 infection was detected on January 20, 2020. However, some serology studies suggest SARS-CoV-2 may have been present in the United States prior to that, as early as December 2019. The extent of domestic COVID-19 detection prior to 2020 has not been well-characterized. Objectives To estimate the prevalence of SARS-CoV-2 antibody among healthcare users in the greater Seattle, Washington area from October 2019 through early April 2020. Study design We tested residual samples from 766 Seattle-area adults for SARS-CoV-2 antibodies utilizing an ELISA against prefusion-stabilized Spike (S) protein. Results No antibody-positive samples were found between October 2, 2019 and March 13, 2020. Prevalence rose to 1.2% in late March and early April 2020. Conclusions The absence of SARS-CoV-2 antibody-positive samples in October 2019 through mid-March, 2020, provides evidence against widespread circulation of COVID-19 among healthcare users in the Seattle area during that time. A small proportion of this metropolitan-area cohort had been infected with SARS-CoV-2 by spring of 2020.
【초록키워드】 COVID-19, SARS-CoV-2, spike, serology, antibody, SARS-COV-2 infection, ELISA, Prevalence, Protein, Cohort, SARS-CoV-2 antibodies, SARS-CoV-2 antibody, healthcare, Study design, United States, circulation, Evidence, Washington, spring, prefusion, Seattle, widespread, objective, Result, greater, tested, proportion, the United State, provide, absence, infected with SARS-CoV-2, 【제목키워드】 Seroprevalence, Seattle,