Updated: April 02, 2020 06:44 PM
Created: April 02, 2020 10:17 AM
(ABC 6 News) -- As researchers continue to develop a vaccine for COVID-19, new serologic testing assays that Dr. Elitza Theel and her team at Mayo Clinic are evaluating will provide information critical to that cause.
“A serologic test, in this case, it’s detecting antibodies to COVID-19, and antibodies are part of our immune response to the infection, so these antibodies will recognize the virus, they’ll bind to it and essentially inactivate and kill it,” Dr. Theel said.
But, it takes time for a person’s body to build up those antibodies. For this virus, Dr. Theel said it seems to take between nine and 11 days.
“Because of that lag time we really cannot use serologic testing to diagnose individuals that are presenting with two-three days of symptoms,” Dr. Theel said.
While the serologic assays would indicate if a patient has already had COVID-19, they are not a replacement for current COVID-19 testing.
“Molecular tests are detecting genetic material from the virus itself that’s found on the swabs that we’re taking from the nose or the mouth, so these assays are detecting the virus itself, whereas serologic assays are detecting an immune response to the virus, and that takes time to develop,” Dr. Theel said.
Her team’s work gets at a different kind of information, which will aid in the development of a vaccine.
“Serologic tests are going to be important for evaluating how well these vaccine candidates are working. So we’re going to have to test individuals who’ve received these vaccines to see if they’ve mounted an immune response and how long that immune response lasts,” Dr. Theel said.
The common cold can produce similar antibodies to COVID-19, which can create a false positive with the serologic test assays.
Dr. Theel and her team have looked at more than 200 people who do not have COVID-19 to try and limit false positives and better understand the specific antibodies that develop for COVID-19.
While there’s still much to learn about the virus, finding out who has already had it and developed the tools to fight it, is a step forward.