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

Abstract

BackgroundA 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.ObjectivesTo evaluate the response and duration for 5 subsets of anti-SARS-CoV-2 antibodies after vaccination and their predictive value for protection.MethodsWe 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.ResultsThe 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) (P<0.05). Participants with anti-Spike IgA seropositivity had 4.314 times greater persistence of neutralizing antibodies than participants without anti-Spike IgA seroconversion (P<0.05).ConclusionsAntibody 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.

Is the fourth COVID-19 vaccine dose urgently needed? Revelation from a prospective cohort study

“…To measure anti-SARS-CoV-2 antibody waning after vaccination, two mixed effects models were fitted. First, the neutralizing antibody, anti-RBD total antibody, and anti-Spike IgG levels declined over time, with half-lives of 81.14 days, 105.66 days, and 104.76 days within 180 days after the third dose, respectively, as esti-mated by an exponential decay model, which increased 2-4 fold compared with those after the second dose 5 and were longer than those within 3 months after the third dose in our previous study. 4 The power law model estimated half-lives for the neutralizing antibody of 293.88 days, anti-RBD total antibody of 468.98 days, and anti-Spike IgG of 467.28 days, which were longer than those estimated by the exponential decay model ( Fig.…”

Strength and durability of antibody responses to BNT162b2 and CoronaVac

“…We found stronger responses to two doses of both vaccines in females and in younger adults, consistent with other studies. For example Uwamino et al reported similar observations in a cohort of 673 recipients of BNT162b2 [13], while Xu et al reported stronger and more durable antibody responses in females and younger recipients of an inactivated vaccine [14]. There are a number of potential underlying biological mechanisms that could lead to a sex difference, and stronger antibody responses in women have been reported for other vaccines [15].…”

The Fluctuation Trend of Serum Anti-SARS-CoV-2 IgM/IgG Antibodies Seroprevalence in the Non-COVID-19 Infected Population and Correlation with Peripheral Blood Leukocyte Parameters in Beijing, China, 2021: A Real-World Study

“…The total seropositivity rate of serum IgM and IgG antibodies in August in the present study population was higher than that in February and March, and the serum IgG and IgM antibody levels gradually decreased over time in September and October. This decline suggested that the IgG antibody could not maintain at a higher level for a longer time in the body, and it is necessary to strengthen vaccination [6,23]. After beginning the booster vaccination at the end of October in Beijing, the IgG antibody seropositivity rate in November increased compared with that in September and October.…”

“…The serum SARS-CoV-2 IgM/IgG antibodies were measured with the magnetic particle chemiluminescence semi-quantitative method by using the AutoLumo A2000 Plus fully automated chemiluminescence Immunoassay analyzer and supporting reagents kits (Autobio Diagnostics Co., Ltd., Zhengzhou, Henan Province of China) [6]. This assay measured the IgM/IgG antibody designed to detect specific IgM/IgG antibodies to the receptor-binding domain (RBD) of the S1 subunit of SARS-CoV-2 spike protein in human serum or plasma.…”