Individuals who were mildly symptomatic following infection with SARS-CoV-2 B.1.1.28 have neutralizing antibodies to the P.1 variant.

Abstract Objectives: To evaluate if antibodies induced by infection with SARS-CoV-2 B.1.128 neutralize the P.1 variant. Methods: Convalescent sera from 60 individuals who had mild symptoms that did not require hospitalization following a documented SARS-CoV-2 infection (B.1.128 lineage) were assayed for neutralizing antibody titer against their original strain and against the SARS-CoV-2 P.1 variant. Results: Fifty-six (94%) and 50 (84 %) sera were positive for neutralizing antibodies against the ancestral and P.1 strains, respectively, and remained positive throughout the 6-week study period. Neutralization titers were consistently higher against the ancestral strain (p[≤] 0.001), but in the majority of patients (57.8%) differences did not differ by more than a single dilution. Conclusions: Neutralizing antibodies that were generated following a mild infection with SARS-CoV-2 B.1.128 were effective in vitro, and likely protective, against the SARS-CoV-2 P.1. variant in the majority of individuals.