LIMA — Lima Memorial Health System is now testing individuals for the presence of Covid-19 antibodies — proteins in the blood that show the body has mounted an immune response to the novel coronavirus, which may confer some level of immunity in those who have already been infected.
The tests, which were developed by Mayo Medical Laboratories, look for the presence of IgG neutralizing antibodies, the antibody that kills the virus.
While scientists are unsure what level of antibodies are needed to ward off future infections, and it is still unclear how long a person holds immunity, those who have recovered from the virus may donate their blood plasma toward an experimental treatment for critically ill Covid-19 patients.
“Since it’s a novel virus, we are in uncharted territory to determine if the antibody they have does in fact offer them future immunity,” said Burlin Sherrick, director of laboratory for Lima Memorial Health System.
The test does not detect active infections, although Lima Memorial and Mercy Health St. Rita’s have been able to test for active infections in suspected Covid-19 patients for weeks, so people seeking an antibody test should be symptom-free for at least 10 days.
And those who do test positive for the presence of antibodies should continue to practice social distancing and take other precautions.
Mercy Health is working with a team of medical experts to evaluate its own antibody testing options. But in a statement on Thursday, the health network said that these tests are still being evaluated and validated by the Food and Drug Administration and that deploying widespread antibody testing will take time.
Wilson Health, and other hospitals around the state, have also started rolling out antibody testing, with or without a doctor’s order, in recent weeks.
Antibody testing may be most useful when used to estimate the prevalence of past Covid-19 infections within a community.
“I think they’re an excellent starting point,” said Dr. Ross Kauffman, an assistant professor of epidemiology and director of public health for Ohio Northern University.
But because there are still questions regarding the reliability of the various antibody tests now on the market, and because there are still so many unknowns regarding immunity to Covid-19, Kauffman cautioned against interpreting a positive result as proof of immunity.
“Even if we can be positive that we have a true positive result, what exactly does that mean? It still creates some challenges.”
Reach Mackenzi Klemann at 567-242-0456.