Antibodies who?

In regards to the current COVID-19 pandemic, there are discussions about testing for antibodies floating around. What does this mean? Basically, antibodies are produced in your body as a response to an infection. Antibodies help to tag infected cells in your body so your immune system can recognize and kill them. The production of antibodies and the certain types can determine if your body has been infected by a certain organism and if you have produced an immune response to it. If your body has been infected and formed an antibody response against the infection, IgM will be the first antibody produced. This happens during the primary infection but it does not create any memory against that certain infection. Once there are IgM and IgG antibodies in your plasma, it means that the antibody response has matured and gone through class switching in order to make antibodies that work better than just IgM alone. It also means that your body has now produced some memory cells on how to fight the infection if it were to reoccur. If your antibody titer has mainly IgG being produced, it means you have already encountered the organism, effectively fought it off, and now have immunity to it due to your memory cells.

This antibody testing is an attempt to gain knowledge on whether someone has been exposed to the virus and what kind of immunity their body has made against it. The testing for antibodies in the blood doesn’t test if you are in active infection with the coronavirus, only if you have been exposed. This would be very helpful to know especially for our healthcare workers that are continually exposed to patients suffering from the virus. Scientists are working to develop a rapid antibody test in order to more efficiently find out the status of antibody response in a patient to figure out a plan for their care. If a person’s blood tests positive for IgG antibodies, their plasma could be given to extremely sick patients as a way to help boost their immunity to the virus. The possibility of this treatment would be a huge step in our fight against this virus.

Determining whether or not a certain person has some immunity against COVID-19 could be vital in returning to a normal life. A lot of patients infected with the virus are asymptomatic, meaning they wouldn’t even know they have been infected. Their body created antibodies and fought off the infection on its own. These people then have a memory immune response against the virus if they contracted it again. This means that these people would be able to return to work without the fear of being infected by others, which would begin our slow movement back into a normal life. The length of immunity against COVID-19 is unknown but scientists believe there is some immunity built up after the first infection.