CDC does NOT recommend that employers use antibody tests to determine which employees can work. Antibody tests check a blood sample for past infection with SARS-CoV-2, the virus that causes COVID-19. CDC does not yet know if people who recover from COVID-19 can get infected again. Viral tests check a respiratory sample (such as swabs of the inside of the nose) for current infection with SARS-CoV-2. CDC has published strategies for consideration of incorporating viral testing for SARS-CoV-2 into a workplace COVID-19 preparedness, response, and control plan. Different states and jurisdictions may have their own guidance and priorities for viral testing in workplaces. Testing in the workplace could be arranged through a company’s occupational health provider or in consultation with the local or state health department.