目的:疫苗诱导的免疫力下降和可能导致免疫逃逸的新型严重急性呼吸综合征冠状病毒-2(SARS-CoV-2)变种的出现,对COVID-19大流行构成重大威胁。目前,针对Omicron变体的加强疫苗接种后产生的中和抗体(NAb)的功效增强是疫苗策略研究的主要重点。在这项研究中,我们分析了感染Omicron变体和野生型(WT)SARS-CoV-2的患者在第三次疫苗剂量后产生的NAb和IgG的效力。
方法:我们招募了75例Omicron变异型突破性感染患者,和87例WT感染患者。我们记录了所有患者的临床特征和疫苗接种信息,并测量了Omicron变异感染患者的血清样本中针对SARS-CoV-2的NAb和抗S1(刺突蛋白)N(核衣壳蛋白)IgG结合抗体。入院时,和WTCOVID-19感染的患者从入院到出院,和一年到两年的随访。
结果:我们的结果显示了更高的NAb水平,临床症状较少,并且在Omicron变体感染的患者中更快的病毒脱落接种了加强剂量的疫苗。混合免疫(自然感染加疫苗接种)诱导比仅疫苗免疫更高的NAb水平。在自然感染的WT康复患者中,NAb和IgG水平在一年的随访中显着下降。加强疫苗接种的COVID-19患者的NAb和IgG水平高于两次疫苗接种的患者。
结论:我们的结果表明,需要加强疫苗接种来提高保护性NAb的水平。此外,我们的数据为基于现有疫苗的疫苗接种策略提供了重要证据.
OBJECTIVE: Waning vaccine-induced immunity and emergence of new severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variants which may lead to immune escape, pose a major threat to the COVID-19 pandemic. Currently, enhanced efficacy of the neutralization antibodies (NAb) produced after the booster dose of vaccinations against the Omicron variant is the main focus of vaccine strategy research. In this
study we have analyzed the potency of the NAbs and IgGs produced after the third vaccine dose in patients infected with Omicron variant and wild-type (WT) SARS-CoV-2.
METHODS: We enrolled 75 patients with Omicron variant breakthrough infections, and 87 patients with WT infections. We recorded the clinical characteristics and vaccination information of all patients and measured the NAb and anti-S1 (spike protein) + N (nucleocapsid protein) IgG-binding antibodies against SARS-CoV-2 in serum samples of Omicron variant-infected patients at admission, and patients with WT COVID-19 infection from the time of admission and discharge, and one-year to two-years follow-ups.
RESULTS: Our results demonstrated higher NAb levels, fewer clinical symptoms, and faster viral shedding in Omicron variant infected patients vaccinated with the booster dose. Hybrid immunity (natural infection plus vaccination) induces higher NAb levels than vaccine-only immunity. NAb and IgG levels decreased significantly at one-year follow-up in WT convalescents with natural infection. The NAb and IgG levels in booster-vaccinated COVID-19 patients were higher than those in two-dose-vaccinated patients.
CONCLUSIONS: Our results suggest that booster vaccinations are required to improve the level of protective NAbs. Moreover, our data provide important evidence for vaccination strategies based on existing vaccines.