Oxford University Hospitals offer SARS-CoV-2 testing to all symptomatic and asymptomatic staff working at four teaching hospitals in Oxfordshire, United Kingdom. SARS-CoV-2 PCR testing of combined nasal and oropharyngeal swab specimens for symptomatic staff (those with new persistent cough, temperature ≥37.8°C, or anosmia or ageusia) was offered beginning on March 27, 2020. Asymptomatic health care workers were invited to participate in voluntary nasal and oropharyngeal swab PCR testing every 2 weeks and serologic testing every 2 months (with some participating more frequently for related studies) beginning on April 23, 2020, as previously described.5 ,22 (link) Staff were followed until November 30, 2020. Deidentified data were obtained from the Infections in Oxfordshire Research Database, which has generic research ethics committee, Health Research Authority, and Confidentiality Advisory Group approvals.