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MHS Offering COVID-19 Antibody Testing achieving 100% Specificity and 100% Sensitivity

McKenzie Health System (MHS) is committed to offering the most accurate testing available to determine if individuals have antibodies for COVID-19. The Ortho Anti-SARS-CoV-2 test, which is available now at MHS, is achieving 100% specificity and 100% sensitivity for the COVID-19 virus and has been validated through a number of studies.

“The Laboratory Department at MHS has worked diligently knowing how great the need is for having accurate testing available. Being able to offer the antibody test with 100% specificity is a significant step forward,” said Nate Petrie, Lab Director at MHS. “I am incredibly proud of the staff and how they have continued to meet the challenges of this time.”

The test for antibodies is done by having blood drawn. An analysis of the blood will show if a person’s body has responded to the virus by producing antibodies. Antibody tests are used to identify people who were previously infected with the COVID-19 virus, helping to pinpoint those who previously had the virus and now have antibodies against it. There are two COVID-19 antibodies that may be present if someone had been infected with COVID-19 and both are detected by the test:

  • The Immediate Response antibody (IgM), which is the first to appear and typically lasts for two or three weeks. The role this antibody plays is to attack the virus and eliminate it.
  • The Memory antibody (IgG) is the second antibody. It appears in the system later and, based on what we know about other antibodies, will most likely be present for the remainder of the person’s life. The role of this antibody is to remember the virus so the body knows how to fight it should it ever return.

“Specificity”, although not a common word outside of the medical community, is important as it has a direct impact on the accuracy of the antibody test. A test that has 100% specificity eliminates “false positives”, meaning it is not fooled by other viruses. If a test is less than 100% specific, the test could indicate the COVID-19 antibody is present, when, in fact, it is an antibody for a different virus. Any drop from 100% specificity impacts the accuracy more significantly than the number indicates. In other words, 99% specificity does not mean 99% accuracy; the accuracy level is lower and every percentage point less widens the gap even more.

Christopher D. Hillyer, MD, President and CEO at New York Blood Center recently shared: “The observed 100% specificity with Ortho’s VITROS SARS-CoV-2 tests allow an extremely high level of confidence so that people will not be identified as having an immune response to the virus when in fact they do not. Statistically, the chance of error rises dramatically even with a very small decline from 100% in specificity, given our understanding of the prevalence of the COVID-19 virus today.”

“Throughout this crisis, the team at MHS has remained focused on being prepared and delivering the highest level of care possible for our community,” said MHS President and CEO Steve Barnett. “We remain dedicated to the health and well-being of our community, our staff, and our patients.”

According to the World Health Organization, about 80% of all coronavirus cases are mild or asymptomatic, which means many people are unaware that they have or have had the virus. While scientists do not know how much immunity the presence of antibodies may provide or how long it will last, individuals with antibodies may be able to donate a plasma or feel more comfortable resuming activities.

For individuals interested in having the antibody test done, they will need an order from their provider. Blood draws can be done at the McKenzie Outpatient Clinic located at 120 Delaware Street in Sandusky. The Outpatient Clinic entrance is on the north side of the hospital and is open Monday through Friday from 7:00 a.m. to 5:00 p.m. The test for the COVID-19 virus can still be done at MHS as well and requires a provider order.

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