Created at	Source	Raw Value	Validated value
April 29, 2021, 10:18 a.m.	usa	inclusion criteria: - has provided written consent for participation - age between 20 and 55 - has a negative nucleic acid-based test result for sars-cov-2 - has a negative antibody test result for sars-cov-2	inclusion criteria: - has provided written consent for participation - age between 20 and 55 - has a negative nucleic acid-based test result for sars-cov-2 - has a negative antibody test result for sars-cov-2