Posted byDr. DougAugust 1, 2020Posted inCOVID-19
https://sciencewithdrdoug.wordpress.com/2020/08/01/is-a-coronavirus-vaccine-a-ticking-time-bomb/?fbclid=IwAR2kyOZXYkErNKNeOZDGwt5wQ1z6yZAdUs8miFAdQi_YhqRT961o-td2OpI Will a vaccine to SARS-CoV-2 actually make the problem worse? Although not a certainty, all of the current data says that this prospect is a real possibility that needs to be paid careful attention to. If you stay with me, I’ll explain why. First, let’s set aside the debate surrounding the topic of whether vaccines work and the negative health consequences due to the components of the vaccine. No matter where you stand on the vaccine issue, I’m not asking anyone to capitulate on this point. I’m just asking that this issue be set aside, because in this instance this argument is completely irrelevant. Even without bringing any other issue into the vaccine debate, a coronavirus vaccine is a highly dangerous undertaking due to a peculiar trojan horse mechanism known as Antibody Dependent Enhancement (ADE). Regardless of someone’s conviction about vaccines, this point needs to be acknowledged. In the remaining portion of this article, I’m going to explain how ADE works and the future perils it may bring. For a vaccine to work, our immune system needs to be stimulated to produce a neutralizing antibody, as opposed to a non-neutralizing antibody. A neutralizing antibody is one that can recognize and bind to some region (‘epitope’) of the virus, and that subsequently results in the virus either not entering or replicating in your cells. A non-neutralizing antibody is one that can bind to the virus, but for some reason, the antibody fails to neutralize the infectivity of the virus. This can occur, for example, if the antibody doesn’t bind tightly enough to the virus, or the percentage of the surface area of the virus covered by the antibody is too low, or the concentration of the antibody is not high enough. Basically, there is some type of generic binding of the antibody to the virus, but it fails to neutralize the virus. In some viruses, if a person harbors a non-neutralizing antibody to the virus, a subsequent infection by the virus can cause that person to elicit a more severe reaction to the virus due to the presence of the non-neutralizing antibody. This is not true for all viruses, only particular ones. This is called Antibody Dependent Enhancement (ADE), and is a common problem with Dengue Virus, Ebola Virus, HIV, RSV, and the family of coronaviruses. In fact, this problem of ADE is a major reason why many previous vaccine trials for other coronaviruses failed. Major safety concerns were observed in animal models. If ADE occurs in an individual, their response to the virus can be worse than their response if they had never developed an antibody in the first place. An antibody can be rendered a non-neutralizing antibody simply because it doesn’t bind to the right portion of the virus to neutralize it, or the antibody binds too weakly to the virus. This can also occur if a neutralizing antibody’s concentration falls over time and is now no longer of sufficient concentration to cause neutralization of the virus. In addition, a neutralizing antibody can subsequently transition to non-neutralizing antibody when encountering a different strain of the virus.