As Covid-19 has become a strong, disruptive force against “everyday life”, many groups have attempted to create new tests that more effectively measure the presence of Covid-19 within a population. One such group that is attempting to develop testing for the virus is at Stanford Medicine School and they have recently developed a new test for Covid-19 that examines plasma for signs of an immune response like antibodies. Unlike the current tests for the virus that examine for the presence of the genetic material of the virus, these tests are specifically screening for Immunoglobulin M (IgM) and Immunoglobulin G (IgG). IgM is an antibody that is made very early in the immune response and its presence in the body quickly declines. On the other hand, the antibody IgG increases slower in the body in response to a pathogen but tends to persist longer in the body.
It is important to check for the presence of antibodies within the body as it is ultimately a large descriptor for how long a person has been infected and how immune they are to reinfection of the virus. For the test developed by Stanford Medicine, the results can read to describe the presence of the individual antibodies, IgM and IgG, as either positive or negative. If someone tests positive for IgM and negative for IgG, it’s possible that they could have recently begun to recover from Covid-19 as the levels of IgG present within the body aren’t detectable. If someone tests negative for IgM and positive for IgG, it is likely that this person has already been infected with the virus and that their body has created an effective response to it that has prevented the person from getting reinfected or infecting others. As tests, such as the one designed by Stanford Medicine, can be used to effectively determine if someone has been infected by the virus even if they were asymptomatic, many have begun to question the information that these screenings can give to researchers and the general public alike.
While the antibody screening tests don’t offer a method for diagnosing early infection of Covid-19, they do offer a way that researchers can measure the presence of an antibody response within a given population. Recently, the CDC has begun an attempt at using these tests to determine who has already been infected by the virus in order to more properly gage the incidence as well as the mortality rate of Covid-19. As one could be asymptomatic or only experience mild symptoms if they are infected with the virus, it is possible that they couldn’t have even known they had contracted the virus and therefore never gone to get tested. This would ultimately skew the data presented about the virus as the full population of people is not considered when examining the virus. As antibody tests for Covid-19 continue to be developed, it’s possible they could be used to determine if someone can return to school or work safely. Ultimately, it’s important to note that these screenings could play a crucial part in determining when the world can return to a seemingly “normal” routine.
Resources
Digitale , Erin. “Test for Antibodies against Novel Coronavirus Developed at Stanford Medicine.” Stanford Medicine , Stanford University, 10 Apr. 2020, http://med.stanford.edu/news/all-news/2020/04/stanford-medicine-develops-antibody-test-for-coronavirus.html.
Mandavilli, Apoorva, and Katie Thomas. “Will an Antibody Test Allow Us to Go Back to School or Work?” New York Times, New York Times, 10 Apr. 2020, https://www.nytimes.com/2020/04/10/health/coronavirus-antibody-test.html.
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