When would that occur? 1-3 years maybe.
If the vaccine targets multiple epitopes, it would generate multiple antibodies and it would take more mutations for the virus to evade them all. maybe 10 years there. Maybe forever.
The risk is that as the virus mutates into new variants, and neutralizing antibody levels decrease, a point may be reached where the antibodies enhance the viruses pathogenicity i.e. Antibody Dependent Enhancement.
We see this with Dengue fever virus. There are 4 variants of DFV. The first time you get it, it's typically mild. If you get it again, it's likely that you will get a different subtype of the virus i.e. a different "variant".When this happens, you are very likely to get the more lethal form of Dengue fever. It has recently been determined that there is also a direct relationship between decreasing antibody levels and this Antibody Enhancement. High levels of Neutralizing antibodies are found to be protective; whereas, decreasing levels of neutralizing antibodies are associated with the more lethal form of Dengue fever in subsequent infections.
Because of this, I think it's likely that we'll end up needing a booster shot to keep neutralizing antibody levels high as the virus mutates into new variants but, once again, it kind of depends on how specific this vaccine is to the original strain i.e. one epitope or multiple epitopes.
Thanks for your thoughts.
I don’t know how many epitopes are targeted by the vaccines. I have often seen the singular “spike protein” used (but “journalists”).
I did see a report that Walter Reed was researching a general purpose coronavirus vaccine, with multiple targets, to cover broad ranges of sub-types or mutations. That was just developmental though.
Maybe mixing and matching the vaccines might be helpful, if they target different epitopes.
“I think it’s likely that we’ll end up needing a booster shot to keep neutralizing antibody levels high as the virus mutates into new variants but, once again, it kind of depends on how specific this vaccine is to the original strain i.e. one epitope or multiple epitopes.
No one knows how long our shots will last. Each of us have an incredible # of variables that will impact that reality.
We an be sure that some testing companies are working on quick tests which will help determine, when we might need another booster shot. Those tests could used at home or at shot clinics to determine if we need a booster and how much.