Chu, Helen Y Early Detection of Covid-19 through a Citywide Pandemic Surveillance Platform. [electronic resource] - The New England journal of medicine 07 2020 - 185-187 p. digital Publication Type: Letter; Multicenter Study ISSN: 1533-4406 Standard No.: 10.1056/NEJMc2008646 doi Subjects--Topical Terms: BetacoronavirusCOVID-19Coronavirus Infections--diagnosisEpidemiological MonitoringHumansPandemicsPneumonia, Viral--diagnosisSARS-CoV-2Washington