OBJECTIVE: In this study, we aimed to conduct a comparative assessment of antibody responses between vaccinated naïve (VN) and unvaccinated naturally infected individuals (NI) over 10 Months.
METHODS: The study comprised fully-vaccinated naïve individuals (VN; n = 596) who had no history of SARS-CoV-2 infection, and received two doses of either BNT162b2 or mRNA-1273, and naturally infected individuals who had a documented history of SARS-CoV-2 infection and no vaccination record (NI cohort; n = 218). We measured the levels of neutralizing total antibodies (NtAbs), anti-S-RBD IgG, and anti-S1 IgA titers among VN and NI up to ∼10 months from administration of the first dose, and up to ∼7 months from SARS-CoV-2 infection, respectively. To explore the relationship between the antibody responses and time, Spearman\'s correlation coefficient was computed. Furthermore, correlations between the levels of NtAbs/anti-S-RBD IgG and NtAbs/anti-S1 IgA were examined through pairwise correlation analysis.
RESULTS: Up to six months, VN individuals had a significantly higher NtAb and anti-S-RBD IgG antibody responses compared to NI individuals. At the 7th month, there was a significant decline in antibody responses among VN individuals, but not NI individuals, with a minimum decrease of 3.7-fold (p < 0.001). Among VN individuals, anti-S1 IgA levels began to decrease significantly (1.4-fold; p = 0.007) after two months, and both NtAb and S-RBD IgG levels began to decline significantly (NtAb: 2.0-fold; p = 0.042, S-RBD IgG: 2.4-fold; p = 0.035) after three months. After 10 months, the most significant decline among VN individuals was observed for S-RBD-IgG (30.0-fold; P < 0.001), followed by NtAb (15.7-fold; P < 0.001) and S-IgA (3.7-fold; P < 0.001) (most stable). Moreover, after 5 months, there was no significant difference in the IgA response between the two groups.
CONCLUSIONS: These findings have important implications for policymakers in the development of vaccination strategies, particularly in the consideration of booster doses to sustain long-lasting protection against COVID-19.
目的:在本研究中,我们的目标是在10个月内对接种疫苗的未接种疫苗的天然感染者(VN)和未接种疫苗的天然感染者(NI)之间的抗体应答进行比较评估.
方法:该研究包括没有SARS-CoV-2感染史的完全接种疫苗的未接种个体(VN;n=596),并接受了两剂BNT162b2或mRNA-1273,以及有SARS-CoV-2感染史且无疫苗接种记录的自然感染者(NI队列;n=218)。我们测量了中和总抗体(NtAbs)的水平,抗S-RBDIgG,和抗S1IgA滴度在VN和NI长达10个月从第一次给药,从SARS-CoV-2感染到7个月,分别。探讨抗体应答与时间的关系,计算Spearman相关系数。此外,通过配对相关分析检测NtAbs/抗S-RBDIgG和NtAbs/抗S1IgA水平之间的相关性。
结果:长达六个月,与NI个体相比,VN个体具有显著更高的NtAb和抗S-RBDIgG抗体应答。在第七个月,VN个体的抗体反应显著下降,但不是NI个人,最小减少3.7倍(p<0.001)。在VN个人中,两个月后,抗S1IgA水平开始显着下降(1.4倍;p=0.007),三个月后,NtAb和S-RBDIgG水平开始显着下降(NtAb:2.0倍;p=0.042,S-RBDIgG:2.4倍;p=0.035)。10个月后,在VN个体中,S-RBD-IgG的下降最为显著(30.0倍;P<0.001),其次是NtAb(15.7倍;P<0.001)和S-IgA(3.7倍;P<0.001)(最稳定)。此外,5个月后,两组的IgA反应无显著差异。
结论:这些发现对制定疫苗接种策略的政策制定者具有重要意义。特别是在考虑加强剂量以维持对COVID-19的长期保护作用时。