The vaccine induced antibodies are measurable, they can have a positive effect. The first trials and numbers about C19 deaths could show some positive effect because they measured recently vaccinated people with high antibody levels and antibodies that targeted exactly the dominant variant. Like all antibodies, vaccine induced antibodies go away in 3-4 months - only some b-cells remain that wake up and produce new antibodies if the virus gets detected. In theory, this should lower the severity of an infection even after 3-4 months. But that was not really measurable (conflicting numbers). Possible reasons: - The virus mutates and evades the vaccine induced antibody set - Until the b-cells wake up, the viral load is identical in vaccinated, unvaccinated and recovered (vaccinated people spread the virus too) - The vaccine induced antibody set is suboptimal: - - Less neutralizing than natural immunity - - More antibody types that do harm (clotting, myocarditis, ..) - - The immune system reacts with an outdated set of antibodies instead of creating antibodies that target the new virus variant - The main problem with SARS-2 is that it can multiply undetected for a few days. The ability to react fast after the detection doesn't help much because the damage is already done (but that doesn't explain why natural immunity works very good). On the other side: The new vaccine technics are not fully developed yet. They kill more people than the virus if antiviral medicine is taken into account. The people who pushed the vaccines have suppressed the medicine as unwanted competition and have killed millions worldwide in the process.