METHODS: The performance of five surrogate NAbs-three chemiluminescent immunoassay (CLIA) and two enzyme-linked immunosorbent assays (ELISAs)-and specific IgM and IgG assays were compared using COVID-19-vaccinated serum (n = 164). Conventional virus neutralization test (cVNT) was used as a criterion and the diagnostic agreement and correlation of the five assays were evaluated. We studied the antibody responses after the two-dose vaccine in volunteers up to 6 months.
RESULTS: The sensitivity and specificity of five surrogate NAb assays ranged from 84% to 100%. Our cVNT results indicated great consistency with the surrogate assays. At 28 days after primary vaccination, the seropositivities of the NAbs, IgG, and IgM were 6%, 4%, and 13%, respectively. After the booster dose, seropositivities reached 14%, 65%, and 97%, respectively. Six months after receipt of the second dose, the NAb positive rate was eventually maintained at 66%. In all COVID-19 convalescents, patients were detected with 100% NAb sat three months after discharge.
CONCLUSIONS: COVID-19 vaccine induced a humoral immune response lasting at least six months. Rapid serological detection was used as a proxy for identifying changes in immunity levels and as a guide to whether an individual may require a booster vaccination.
方法:使用COVID-19疫苗接种血清(n=164)比较了5种替代NAb-3种化学发光免疫测定(CLIA)和两种酶联免疫吸附测定(ELISA)以及特异性IgM和IgG测定的性能。以常规病毒中和试验(cVNT)为标准,评价5种试验的诊断一致性和相关性。我们在志愿者中长达6个月的两剂量疫苗后研究了抗体反应。
结果:五种替代NAb测定的灵敏度和特异性范围为84%至100%。我们的cVNT结果表明与替代测定非常一致。初次接种疫苗后28天,NAs的血清阳性,IgG,IgM为6%,4%,13%,分别。加强剂量后,血清阳性率达到14%,65%,97%,分别。在接受第二次剂量六个月后,NAb阳性率最终维持在66%.在所有COVID-19疗养院中,患者在出院后3个月检测到100%NAb.
结论:COVID-19疫苗诱导了持续至少6个月的体液免疫应答。快速血清学检测被用作识别免疫水平变化的代理,并作为个体是否需要加强疫苗接种的指导。