Thank you for donating blood through the American Red Cross. During the blood donation process, samples are collected and sent to a laboratory where they undergo routine screening and infectious disease testing. The Red Cross is also testing donations for antibodies to the SARS coronavirus-2 (SARS-CoV-2), the virus that causes COVID-19, using the Ortho VITROS® Anti-SARS-CoV-2 IgG Quantitative test. This test is authorized for use by the U.S. Food and Drug Administration through its Emergency Use Authorization (EUA) mechanism.
Testing may identify the presence of antibodies developed after past exposure to the virus that causes COVID-19 – regardless of whether a person developed symptoms – or from receiving a COVID-19 vaccine. It takes one to three weeks after an infection or vaccination to reach a detectable level of antibodies. At this time, it is unknown for how long COVID-19 antibodies persist following infection or vaccination, and what level of antibodies offers protective immunity against any given variant of the COVID-19 virus.