Earlier quoted context omitted.
Vaccination has been shown to induce an immune response including T cells [1]. However, vaccination induces a slightly different immune response compared to natural infection [2][3] . These differences may account for variation in effectiveness between vaccine-induced and naturally acquired immunity. [1] Rapid induction of antigen-specific CD4+ T cells is associated with coordinated humoral and cellular immune respon…
> differences may account for variation in effectiveness between vaccine-induced and naturally acquired immunity. What's the variation you are referring to?
It's all preliminary data. However, the sinopharm vaccine, which is the whole virus, not just spike protein, seems to lose effectiveness after several months as well.