Department of Laboratory Medicine, Biobank, ASST Papa Giovanni XXIII, Bergamo, Italy.
Department of Laboratory Medicine, Microbiology and Virology, ASST Papa Giovanni XXIII, Bergamo, Italy.
J Med Virol. 2021 Jul;93(7):4612-4615. doi: 10.1002/jmv.26982. Epub 2021 Apr 8.
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic calls for rapid actions, now principally oriented to a world-wide vaccination campaign. In this study we verified if, in individuals with a previous SARS-CoV-2 infection, a single dose of messenger RNA (mRNA) vaccine would be immunologically equivalent to a full vaccine schedule in naïve individuals. Health care workers (184) with a previous SARS-CoV-2 infection were sampled soon before the second dose of vaccine and between 7 and 10 days after the second dose, the last sampling time was applied to SARS-CoV-2 naïve individuals, too. Antibodies against SARS-CoV-2 were measured using Elecsys Anti-SARS-CoV-2 S immunoassay. The study was powered for non-inferiority. We used non parametric tests and Pearson correlation test to perform inferential analysis. After a single vaccine injection, the median titer of specific antibodies in individuals with previous coronavirus disease 2019 was 30.527 U/ml (interquartile range [IQR]: 19.992-39.288) and in subjects with previous SARS-CoV-2 asymptomatic infection was 19.367.5 U/ml (IQR: 14.688-31.353) (p = .032). Both results were far above the median titer in naïve individuals after a full vaccination schedule: 1974.5 U/ml (IQR: 895-3455) (p < .0001). Adverse events after vaccine injection were more frequent after the second dose of vaccine (mean: 0.95; 95% confidence interval [CI]: 0.75-1.14 vs. mean: 1.91; 95% CI: 1.63-2.19) (p < .0001) and in exposed compared to naïve (mean: 1.63; 95% CI: 1.28-1.98 vs. mean: 2.35; 95% CI: 1.87-2.82) (p = .015). In SARS-CoV-2 naturally infected individuals a single mRNA vaccine dose seems sufficient to reach immunity. Modifying current dosing schedules would speed-up vaccination campaigns.
严重急性呼吸综合征冠状病毒 2 (SARS-CoV-2) 大流行需要迅速采取行动，目前主要方向是在全球范围内开展疫苗接种运动。在这项研究中，我们验证了在先前感染过 SARS-CoV-2 的个体中，单次信使 RNA (mRNA) 疫苗接种是否在免疫上等同于未接种个体的完整疫苗接种方案。在接种第二剂疫苗前，我们对 184 名有既往 SARS-CoV-2 感染的医护人员进行了采样，并在接种第二剂疫苗后 7 至 10 天进行了采样，最后一次采样时间也应用于 SARS-CoV-2 未接种个体。使用 Elecsys Anti-SARS-CoV-2 S 免疫分析测定抗 SARS-CoV-2 抗体。该研究的目的是为了进行非劣效性检验。我们使用非参数检验和皮尔逊相关检验进行推断分析。在单次疫苗接种后，有既往 2019 年冠状病毒病的个体的特异性抗体的中位数滴度为 30.527 U/ml（四分位距 [IQR]：19.992-39.288），有既往 SARS-CoV-2 无症状感染的个体为 19.367.5 U/ml（IQR：14.688-31.353）（p=0.032）。这两个结果都远高于完整疫苗接种方案后未接种个体的中位数滴度：1974.5 U/ml（IQR：895-3455）（p<0.0001）。与第二剂疫苗相比，接种疫苗后的不良反应更为常见（平均：0.95；95%置信区间 [CI]：0.75-1.14 与平均：1.91；95% CI：1.63-2.19）（p<0.0001），与未接种疫苗相比，暴露于疫苗的个体的不良反应更为常见（平均：1.63；95% CI：1.28-1.98 与平均：2.35；95% CI：1.87-2.82）（p=0.015）。在 SARS-CoV-2 自然感染者中，单次 mRNA 疫苗剂量似乎足以达到免疫力。修改当前的剂量方案将加快疫苗接种运动。
