Created at	Source	Raw Value	Validated value
June 25, 2024, noon	usa	study inclusion criteria; * written informed consent * healthcare workers at nursing homes with resident contact * willingness to adhere to study protocol additional inclusion criteria for primary objective 2 (reinfection after vaccination) - sars-cov-2 vaccination list the study	study inclusion criteria; * written informed consent * healthcare workers at nursing homes with resident contact * willingness to adhere to study protocol additional inclusion criteria for primary objective 2 (reinfection after vaccination) - sars-cov-2 vaccination list the study
April 1, 2021, 12:31 a.m.	usa	study inclusion criteria; - written informed consent - healthcare workers at nursing homes with resident contact - willingness to adhere to study protocol additional inclusion criteria for primary objective 2 (reinfection after vaccination) - sars-cov-2 vaccination list the study	study inclusion criteria; - written informed consent - healthcare workers at nursing homes with resident contact - willingness to adhere to study protocol additional inclusion criteria for primary objective 2 (reinfection after vaccination) - sars-cov-2 vaccination list the study