As more and more people in the United States get vaccinated against COVID-19, the number of new cases is falling each day. However, these vaccines are not 100% effective. The Pfizer-BioNTech and Moderna vaccines have efficacy rates of 94%-95%, which, while very high, still leads to the implication that, out of every 100,000 persons receiving these vaccines, 5,000 – 6,000 people will not be protected from COVID-19. This means that some individuals who receive the vaccine may be unaware they’ve failed to develop COVID-19 immunity.
The goal of the vaccines is to train the body to evoke adaptive immune response which typically produces virus specific neutralizing antibodies and T-cells. The neutralizing antibodies have been shown in the scientific literature to be able to block the virus entry and prevent infection and are expected to be good biomarker for immunity.