Researchers at the University of Minnesota Medical School have developed a test for antibodies to the SARS-CoV-2 virus—the agent that causes COVID-19—that uses routine laboratory supplies not in high demand.
In concert with the U of M’s PCR (polymerase chain reaction, a technique to detect specific DNA or RNA sequences) test for the presence of viral material, the new antibody test will allow a person’s infection status to be determined with much greater precision, helping equip the state to confidently send people back to work. Employees at M Health Fairview Bethesda Hospital, who are part of the frontline defense against the virus, will be the first beneficiaries of the new test.
Here’s how the two tests work to categorize an infection status:
If the PCR and antibody tests are both negative, the person has not been exposed to the virus and should practice social distancing and stay home.
If the PCR is positive and the antibody test is negative, the person is in an early stage of infection—that is, they haven’t yet produced antibodies to the virus. They could infect others, and so must be quarantined.
If both tests are positive, the person is in a later stage of infection and must be quarantined.
If only the antibody test is positive, it’s a sign of a past infection but there’s no active virus and the person would be—presumably—immune to further infection and fit to return to work.
Amy Karger, an assistant professor in the Department of Laboratory Medicine and Pathology, leads a team at the U of M’s Advanced Research and Diagnostic Laboratory, which brought the test from a research setting into clinical use. Other major collaborators are Marc Jenkins, Regents and Distinguished McKnight University Professor in the Department of Microbiology and Immunology, and Fang Li, associate professor in the Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine. The antibody test is a type of ELISA, or enzyme-linked immunoabsorbent assay.