Abstract
Previous reports demonstrated that severe acute respiratory syndrome coronavirus (SARS-CoV-2) binding immunoglobulin G levels did not increase significantly between the first and second doses of the BNT162b2 vaccine in previously infected individuals. We tested neutralizing antibodies (nAbs) against SARS-CoV-2 Delta and Omicron variants after the first and second doses of this vaccine in infection-naive and previously infected individuals. Delta, but not Omicron, nAb titers significantly increased from the first to the second dose in both groups of individuals. Importantly, we found that Omicron nAb titers were much lower than Delta nAb titers and that even after 2 doses of vaccine, 17 of 29 individuals in the infection-naive group and 2 of 27 in the previously infected group did not have detectable Omicron nAb titers. Infection history alone did not adequately predict whether a second dose resulted in adequate nAb. For future variants of concern, the discussion on the optimal number of vaccine doses should be based on studies testing for nAb against the specific variant.
Keywords: Delta; Omicron; SARS-CoV-2; antibodies; neutralization; vaccine; variants of concern.
【저자키워드】 antibodies, SARS-CoV-2, Vaccine, neutralization, Delta, omicron, variants of concern., 【초록키워드】 neutralizing antibody, BNT162b2 vaccine, coronavirus, variant, variants of concern, vaccine dose, Immunoglobulin, predict, NAb, binding, dose, acute respiratory syndrome, second dose, infected individuals, individual, significantly increased, tested, significantly, detectable, demonstrated, individuals, much lower, in both group, 【제목키워드】 B.1.617.2, coronavirus 2, activity, B.1.1.529, respiratory, individual, of BNT162b2,