Antibody tests, also called serological tests, test if the individual has been exposed to SARS-CoV-2, the novel coronavirus that causes COVID-19.
Ortho Clinical Diagnostics announced the U.S. Food and Drug Administration (FDA) has granted its total antibody assay for COVID-19 Emergency Use Authorization.
Antibody tests, also called serological tests, test if the individual has been exposed to SARS-CoV-2, the novel coronavirus that causes COVID-19. It does not test if the patient has the disease, but rather if they had it and developed an immune response, which should provide immunity against the disease, although health authorities are not completely sure if or for how long that immunity will last.
The idea is that if people have developed immunity, they can return to a more normal life without worry of catching the disease. The tests can also be used to screen plasma donations for convalescent plasma therapy, which is believed to help critically ill COVID-19 patients fend off the virus. Wide antibody screening is considered essential for moving the world back to some level of normalcy.
The Ortho test is the VITROS Immunodiagnostic Products Anti-SARS-CoV-2 Total Reagent Pack and Calibrators. It is a high-throughput, automated COVID-19 antibody test. It can be run on the company’s laboratory analyzer, the VITROS XT 7600 Integrated System, the VITROS 3600 Immunodiagnostic System, the VITROS 5600 Integrated System and soon the VITROS ECi/ECiQ Immunodiagnostic Systems. These are already in use in more than 1,000 hospitals and reference labs in the U.S.
Already, some test kits have been shipped to high-priority areas. Ortho expects full production in a few weeks, with plans to manufacture several million tests over the next month, with rapid expansion afterwards.
“The COVID-19 pandemic continues to impact individuals, families, and communities around the world,” said Chris Smith, Ortho’s chief executive officer. “Ortho is proud to be working toward large-scale solutions that will help people return to work, reducing the strain on both employees and the economy as a whole. Our focus on improving patients’ lives through diagnostics led us to rapidly develop this test, providing one of the key resources needed for diagnosing and treating COVID-19. We remain committed to helping laboratories deliver fast, accurate, reliable results to healthcare professionals, patients and researchers developing the long-term, sustainable management of this disease.”
The test can identify both IgG and IgM antibodies. IgM typically shows up early in the immune response, but the levels quickly drop; IgG antibodies increase more slowly after an infection, but generally stick around longer.
In some cases, it can take 10 to 11 days for an individual’s immune system to attack the virus and produce the antibodies. This is why the antibody tests aren’t used to diagnose patients with COVID-19 that have shown symptoms within the last two or three days.
On April 3, the U.S. Food and Drug Administration (FDA) approved the first blood test for antibodies against COVID-19. That was by Research Triangle Park, North Carolina-based Cellex. About the same time, Mayo Clinic developed its own antibody test and began offering it on April 6.
Stanford Medicine researchers joined the list of organizations that have developed an antibody test, which was launched April 6 at Stanford Health Care. It is different from an externally developed test Stanford utilized for a prevalence study during a community screening event.
