National Jewish Health continues to increase its testing capabilities for COVID-19 antibodies, including the addition of new validated testing equipment. Ongoing testing and increased capacity will help doctors and researchers gain a better understanding of the extent of the COVID-19 pandemic, as well as meet the demand of the general public who want to know if they’ve had the virus. Since launching in April, National Jewish Health has performed more than 15,000 antibody tests and can now process more than 1,000 COVID-19 antibody blood samples each day.
“Reliable antibody testing provides important information about COVID-19 prevalence rates as we return to normal business and social operations,” said Stephen Frankel, MD, executive vice president of Clinical Affairs at National Jewish Health. “Our ability to test more people increases our knowledge of who has been exposed and recovered from prior infection and also helps inform public health officials’ understanding around the spread of the virus.”
Antibody tests, also known as serology tests, detect antibodies in the blood, which indicate that a person has had COVID-19 and mounted an immune response to the virus that causes it. National Jewish Health offers serology tests for both IgM and IgG antibodies and can detect these antibodies to the virus in blood serum that is collected with a simple blood draw.
In addition to the epidemiological reasons for antibody testing, there is significant interest from the public for a reliable antibody test. Many individuals that were sick earlier this year are interested to know if their illness could have been COVID-19, and others want to know if they might have been asymptomatic carriers.
“There has been incredible demand for antibody testing since we began offering the test to the public earlier in the spring. People are really interested to know if they may have had undetected COVID-19,” said Dr. Frankel.
For the general public, National Jewish Health offers the IgG antibody test which requires an appointment but not a doctor’s order. The test detects IgG antibodies that, in most patients, develop 7 to 21 days after symptoms of COVID-19 begin. IgG antibodies remain in the blood after an infection has passed. They indicate that a person has had COVID-19 in the past and has developed antibodies that may protect from future infection. The extent of immunity is unknown at present and is under active investigation.
The IgM antibody test is offered through a physician order. IgM is the first antibody produced by the immune system when a virus attacks and usually develops before an IgG response. A positive IgM test indicates that a person has been infected. While IgM may be positive in a person with prior infection, it may also be positive in a person who is still infected and has just begun to have an immune response to the virus.
National Jewish Health is currently running SARS-CoV-2 antibody tests supplied by Epitope Diagnostics Inc. and Abbott. Both tests have been validated and refined at the National Jewish Health Advanced Diagnostic Laboratories, a high-complexity CLIA-approved facility. Abbott has reported a sensitivity for its IgG test of 100 percent and specificity of 99.6 percent, which has been confirmed at National Jewish Health. National Jewish Health validation studies indicate that the Epitope Diagnostics IgG test has a specificity of greater than 99 percent and a sensitivity of 95.7 percent.