Abstract
Objectives: The aim of the present study was to evaluate if neutralizing antibody responses induced by infection with the SARS-CoV-2 strain that was dominant at the beginning of the pandemic or by the Gamma variant was effective against the Omicron variant.
Methods: Convalescent sera from 109 individuals, never exposed to a SARS-CoV-2 vaccine, who had mild or moderate symptoms not requiring hospitalization following either a documented SARS-CoV-2 ancestral strain infection or a Gamma variant infection, were assayed for in vitro neutralizing antibody activity against their original strains and the Omicron variant.
Results: Following an infection with the ancestral strain, 56 (93.3%), 45 (77.6%) and 1 (1.7%) serum sample were positive for neutralizing antibodies against the ancestral, Gamma variant, and Omicron variant, respectively. After infection with the Gamma variant, 43 (87.8%) and 2 (4.1%) sera were positive for neutralizing antibodies against the Gamma and Omicron variants, respectively.
Conclusions: Neutralizing antibodies generated following mild or moderate infection with the SARS-CoV-2 ancestral strain or the Gamma variant are not protective against the Omicron variant.
Keywords: Gamma variant; Neutralizing antibodies; Omicron variant; Protective antibodies; SARS-CoV-2.
【저자키워드】 SARS-CoV-2, Neutralizing antibodies, Gamma variant, protective antibodies, Omicron variant, 【초록키워드】 neutralizing antibody, SARS-CoV-2, pandemic, Hospitalization, antibody, variant, Infection, Symptom, in vitro, omicron, variants, SARS-CoV-2 vaccine, serum, sera, Gamma, Mild, moderate, Neutralizing antibody response, Protective, strain, positive, dominant, effective, evaluate, individuals, the SARS-CoV-2, 【제목키워드】 neutralizing antibody, variant, SARS-CoV-2 variant, SARS-CoV-2 virus, omicron, Gamma, convalescent sera, individual,