What COVID-19 antibody testing means for your family
Initial data from widespread antibody testing is beginning to surface. The results are what many of us have speculated all along. Far more people have come in contact with this virus over a period of many months. For some, this statement may be concerning. This means there are more people sick and more carriers, which could mean more distancing and more quarantine, but there is another more positive side to this discussion.
Before we get into the specifics, we need to cover some basics. In medicine, we have a knack for skirting around the complete truth. I’m not sure if this is intentional or if omitting some information just makes the conversation more relatable. Either way, it’s time to change that and lift the curtain on antibody testing.
Antibodies are produced by your white blood cells, specifically plasma cells. They are also called immunoglobulins (Ig). These immunoglobulins come in many flavors and are part of the adaptive immune system. This is an important note, because the adaptive immune system is a bit slower to respond to an infection, making antibody testing not as useful in the first couple of weeks after an exposure. There are 2 major antibodies we will talk about now, Immunoglobulin M (IgM) and Immunoglobulin G (IgG).
Think of IgM as your first responder antibody, it shows up early on, gets things under control and then passes the job onto IgG. Being that IgM is usually only around for a few weeks, we can use this marker to estimate how new or old the infection is. IgG will take over as IgM slowly falls. IgG should remain elevated, to a certain extent, for the rest of the patient’s life. So, in theory, a positive IgG antibody test to SARS-CoV-2 would mean that you have built antibodies to the virus and are considered “immune” to said virus. Theoretically possessing antibodies to the virus, your second encounter shouldn’t be nearly as significant as the first. We have applied this theory for decades in medicine. It is interesting how this interpretation is under scrutiny for this particular virus. This is the same way vaccine efficacy is determined.
The initial perils of the SARS-CoV-2 specific antibody tests are attributed to the style of testing. Most of the skepticism stems from the form of testing that was initially used, which is what is known as ‘lateral flow.’ In short, this methodology is similar to an at-home pregnancy test. In this case, a sample of blood is dropped on one side of the cassette, and the results are shown on the other after the sample has flowed through. It reports as just a positive or negative. Our initial internal testing produced mixed results, plus most of these testing kits are being manufactured in China, which poses an availability issue among other potential problems.
Today, we are using more traditional laboratory methods that are available from many labs across the country. Over the past month, we have seen the accuracy of these tests improve tremendously as they have worked to a create a test that was highly specific for SARS-CoV-2.
Antibody testing is not only important clinically but can also help us to understand the gravity of what we are dealing with. At the time of this article, there have been pockets of testing in various parts of the country. Los Angles has run a pilot study on 863 people. With the results from this study, they have estimated that their original projection of those infected are, in fact, way off. They estimate that there may be up to 55 times more cases than originally estimated. NY has echoed these findings, commenting that 1 in 5 New Yorkers (located in NYC) display antibodies to the virus. In the Marion Correctional Institution located in Ohio, 2,300 inmates (of the 2,500 total) were tested for SARS-CoV-2. 2,028 of the inmates tested positive, with close to 95% having no symptoms. In the coming weeks, we will see scenarios like this play out across the country.
Nationwide antibody testing could quench public fear and change the current narrative. These new-found cases challenge the published mortality rate and provide insight into potential exposure and immune status of the patient. Ultimately, we may be able to return your health care autonomy.
This is a chance to reflect on previous lifestyle and habits. Many patients fall ill because their immune function is suboptimal. This virus, and nearly all other human viruses, will affect those with weakened immune systems the worst. Now is the time to game plan on how to keep your family safe, not only now, but far into the future. There will always be viruses, some even more dangerous than this one; we must be ready for the unexpected.
Eat well, get fresh air and spend time with family and friends. We have an opportunity to come out of this mess stronger than we entered and that is the true silver lining.
Dr. Brett Wisniewski MS, DC, DABCI, DACBN is the clinic director of Gateway Natural Medicine & Diagnostic Center, a Berthoud based business for over 22 years. The clinic offers a variety of services from direct lab access to chronic and urgent care. For any questions please call 970-532-2755.