COVID-19 antibody tests: 9 answers to commonly asked questions

COVID-19 antibody tests: 9 commonly asked questions


Many people have questions about COVID-19 antibody tests. Below are fact-checked answers from Nebraska Medicine experts. 

If you need a quick refresher, this article by Jasmine Marcelin, MD, explains how antibody tests help us track COVID-19.

1.    Are antibody tests available today?

Currently, antibody tests are available at Nebraska Medicine for ordering by a physician. If you’ve had COVID-19, and believe an antibody test would help you make an informed decision, then talk to your physician. They will ask you for the reason to get the antibody test – such as a requirement before going back to work or caring for an immunocompromised family member. If you’d like a COVID-19 antibody test, talk to your primary care provider.

2.    Do antibodies give immunity from COVID-19?

Researchers are studying whether antibodies can prevent COVID-19 infection for a second time. That is, if you’ve had COVID-19 once and your body produced antibodies, are you immune from getting COVID-19 a second time? Whether COVID-19 antibodies provide immunity is still a worldwide question. Antibody immunity is how vaccines work. Studies in animals suggest antibodies to COVID-19 will be protective in humans. 

3.    Are antibody tests accurate?

Several manufacturers have created very different tests. Recently, the CDC advised that many antibody tests might not be accurate. Some COVID-19 antibody tests might say people have antibodies when they don’t or vice versa. These are called false positives and false negatives. An antibody test is only useful information if it’s accurate. The Nebraska Medicine laboratory rigorously investigates the quality of a test before putting it into service.

4.    When will widespread antibody testing be available?

After confirmation is obtained that antibodies give immunity and prevent reinfection, antibody testing will become more widespread. There are accurate, reliable antibody tests today – the  medical community just doesn’t know what the results indicate at this time. We’re doing a few trial runs with small businesses and health care workers to see whether antibodies are common in people who previously tested positive for infection.

5.    Why does evaluating antibody tests take time?

UNMC researchers like Steven Hinrichs, MD, are evaluating COVID-19 antibody tests from different manufacturers, which takes time. “We compared results from four antibody test kits,” says Dr. Hinrichs. “Each kit detected different types or multiple types of antibodies, including IgG, IgM and IgA. We compared the results of the tests to determine which gave the most accurate set of data.” Dr. Hinrichs’ team is evaluating the tests using careful controls, like samples collected before the pandemic even started. 

6.    Can you donate blood if you’ve had COVID-19?

Yes! Blood donation from people who have recovered from COVID-19 helps the entire community. You can donate to the Nebraska Community Blood Bank. Dr. Hinrichs says, “We’re looking for blood donations from anyone who has recovered from COVID-19, but especially those with a mild illness.” To protect the health care workers collecting your blood, wait two weeks after you’ve made a full recovery to donate blood.

7.    Does everyone infected with COVID-19 produce antibodies?

According to Dr. Hinrichs, “Some COVID-19 patients have not made antibodies even after several months, while others make a high amount of antibodies.  Perhaps it depends on the severity of the disease.” More studies are needed in this area. 

8.    Can antibodies be used to treat COVID-19 patients?

Some Omaha and Kearney physicians have treated COVID-19 patients with blood from recovered patients, with promising initial results. The first human trial using donated blood to treat COVID-19 started June 1

9.    Can I get infected by a COVID-19 blood sample?

COVID-19 does not spread through blood. COVID-19 spreads through respiratory droplets from a person with COVID-19. So a blood sample from an infected COVID-19 patient will not infect you. This also means that mosquitos or ticks can’t transmit the coronavirus to a human.