Response and Duration of Serum Anti-SARS-CoV-2 Antibodies After Inactivated Vaccination Within 160 Days

• Published in: Frontiers in immunology Vol. 12; p. 786554
• Main Authors: Xu, Qiu-Yan, Xue, Jian-Hang, Xiao, Yao, Jia, Zhi-Juan, Wu, Meng-Juan, Liu, Yan-Yun, Li, Wei-Li, Liang, Xian-Ming, Yang, Tian-Ci
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 23.12.2021
• Subjects: Adult; anti-SARS-CoV-2 antibody; Antibodies, Neutralizing - blood; Antibodies, Viral - blood; CoronaVac; COVID-19; COVID-19 - immunology; COVID-19 Vaccines - immunology; Female; Humans; Immunization, Secondary; Immunoglobulin A - blood; Immunoglobulin G - blood; Immunoglobulin M - blood; Immunology; Male; neutralizing antibody; SARS-CoV-2; SARS-CoV-2 - immunology; Spike Glycoprotein, Coronavirus - immunology; Time Factors; Vaccination; Vaccines, Inactivated - immunology; COVID-19; neutralizing antibody; SARS-CoV-2; CoronaVac; anti-SARS-CoV-2 antibody
• ISSN: 1664-3224; 1664-3224
• DOI: 10.3389/fimmu.2021.786554

A vaccine against coronavirus disease 2019 (COVID-19) with highly effective protection is urgently needed. The anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody response and duration after vaccination are crucial predictive indicators. To evaluate the response and duration for 5 subsets of anti-SARS-CoV-2 antibodies after vaccination and their predictive value for protection. We determined the response and duration for 5 subsets of anti-SARS-CoV-2 antibodies (neutralizing antibody, anti-RBD total antibody, anti-Spike IgG, anti-Spike IgM, and anti-Spike IgA) in 61 volunteers within 160 days after the CoronaVac vaccine. A logistic regression model was used to determine the predictors of the persistence of neutralizing antibody persistence. The seropositivity rates of neutralizing antibody, anti-RBD total antibody, anti-Spike IgG, anti-Spike IgM, and anti-Spike IgA were only 4.92%, 27.87%, 21.31%, 3.28% and 0.00%, respectively, at the end of the first dose (28 days). After the second dose, the seropositivity rates reached peaks of 95.08%, 100.00%, 100.00%, 59.02% and 31.15% in two weeks (42 days). Their decay was obvious and the seropositivity rate remained at 19.67%, 54.10%, 50.82%, 3.28% and 0.00% on day 160, respectively. The level of neutralizing antibody reached a peak of 149.40 (101.00-244.60) IU/mL two weeks after the second dose (42 days) and dropped to 14.23 (7.62-30.73) IU/mL at 160 days, with a half-life of 35.61(95% CI, 32.68 to 39.12) days. Younger participants (≤31 years) had 6.179 times more persistent neutralizing antibodies than older participants (>31 years) ( <0.05). Participants with anti-Spike IgA seropositivity had 4.314 times greater persistence of neutralizing antibodies than participants without anti-Spike IgA seroconversion ( <0.05). Antibody response for the CoronaVac vaccine was intense and comprehensive with 95.08% neutralizing seropositivity rate, while decay was also obvious after 160 days. Therefore, booster doses should be considered in the vaccine strategies.