Tea F, Stella AO, Aggarwal A, et al. - For understanding reinfection risk and breakthrough infection following vaccination, it is essential to determine the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody neutralization response and its evasion by emerging viral variants and variant of concern (VOC).

• Analysis of 807 serial samples from 233 individuals diagnosed with COVID-19 was performed.

• COVID-19 severity was identified to be linked with a broad and sustained polyantigenic immunoreactivity against SARS-CoV-2 Spike, Membrane, and Nucleocapsid proteins, along with high viral neutralization.

• High neutralizing responses were maintained over time in a subgroup of “high responders”; these represent ideal convalescent plasma donors.

• Antibodies produced against SARS-CoV-2 during the first COVID-19 wave showed decreased immunoreactivity and neutralization potency to emerging Spike variants and VOC.

• For selection of optimal responders and vaccine monitoring and design, accurate monitoring of SARS-CoV-2 antibody responses is suggested as essential.