A Short Course on COVID-19 Immunity and Testing
Or: Why the Vice President “I tested negative” should wear a mask
Types of Testing for COVID-19 Immunity
There are two types of COVID-19 tests: molecular and serological. Molecular tests (PCR) look for the presence of a virus’s genetic material, showing that there is an active infection. Those are the tests that require a swab to be shoved through the back of your nose and into your throat to collect a specimen. While the Molecular PCR test has a higher rate of sensitivity than the serological, it will only show infection, not if the person has the IgG antibody. The IgG antibody is present after a person had the COVID-19 virus and successful fought off the virus, hopefully having immunity now. Serological tests (Rapid Antibody) look for antibodies to the virus in the blood, the presence of (IgG) which indicates there was an infection in the past. It will also show the (IgM) antibody which demonstrates the person is currently infected with the virus and fighting off the infection.
While the molecular tests (PCR) for COVID-19 have been around since the beginning of February, serological tests weren’t authorized until April 1. Many people see these tests as a way to prove immunity against the virus, allowing those who test positive and possess the IgG antibody “only” to resume their normal lives, free from the threat of contracting the virus again. We don’t yet know for sure that these antibodies confer immunity, nor for how long that immunity lasts if they do, but past history of SARS infections, people who possessed the antibody after successfully fighting off that infection had built up immunity for 2-3 years. Enough time until a vaccine is developed for COVID-19.
If a test identifies individuals who have the IgG antibody, it means they successfully fought off the virus and may have immunity if they were to come into contact with someone who has the COVID-19 virus, or when the virus comes back in the Fall. Additionally, it will show who currently has it and if their body is fighting the virus off, the IgM marker. IgG is the more important antibody class, since IgM secreting patients might not seroconvert. IgG positive patients doesn’t mean they can’t be reinfected- the jury is still out on that one.
COVID-19 and Comparative Religion
On a lighter note, long ago at the University of Illinois in Urbana/Champaign, once I had been accepted to Medical School, after having completed a very intense, mandatory, at the time premed curriculum, I decided to seek an education and, took a course, in Comparative Religions. Most immigrants and their first-generation American children grew up in relatively closed communities; it was time for me to see the world. Below is a teaching that might have, or could have, come from that course:
When it comes to the prohibition of eating bats, it seems the Torah repeats the prohibition not just once but twice. Regarding the Hebrew word tinshames (Leviticus, 11:18), Rashi says “it resembles a mouse and flies about at night.” Clearly, a bat.
Then, just one verse later, the Bible prohibits the consumption of an atalef, which is also translated as bat. Is this a biblical warning against the dangers of eating these creatures?
Tags: coronavirus immunity, COVID-19, covid-19 immunity, covid-19 testing, immunity and testing for COVID-19