National Influenza Centre, Edificio Rondilla, Hospital Clínico Universitario de Valladolid, Valladolid, Spain.
Instituto de Estudios de Ciencias de la Salud de Castilla y León, (ICSCYL), Soria, Spain.
Front Immunol. 2023 Feb 22;14:1128302. doi: 10.3389/fimmu.2023.1128302. eCollection 2023.
The third dose of the COVID-19 vaccine is especially necessary in people over 65 years of age due to their lower immune response.
We designed a multicentre, prospective observational study including 98 people ≤65 years old who lived in two nursing homes in Valladolid, Spain. One of the groups had previous experience with SARS-CoV-2 (n=68;69.4%) and the other was naïve (n=30;30.6%). We evaluated the response to the three doses of the Comirnaty vaccine and the dynamics of antibodies during 5 consecutive serum samplings: 2 after the first two doses of vaccination, one three months after the first dose, another at 6 months and the last one month after the third dose. IgG antibodies against SARS-CoV-2 S1, RBD and N antigens were analysed.
Both groups increased the level of Abs against S1 and RBD, but the experienced group showed a 130-fold higher humoral response due to hybrid immunisation (infection+vaccination). The response to vaccination with Comirnaty against COVID-19 was higher in those ≤65 years with previous experience than those who were naïve. However, the amount of antibodies against S1 and RBD equalised at 6 months. After the third dose, both groups raised the amount of antibodies to a similar level. The reinfections suggested by the analysis of antibodies against N were frequent in both groups.
The third dose showed a clear benefit for elderly people, with the reinforcement of the antibody levels after the decline suffered after six months of the first two doses.
由于免疫反应较低，COVID-19 疫苗的第三剂尤其对 65 岁以上人群非常必要。
我们设计了一项多中心、前瞻性观察研究，纳入了 98 名居住在西班牙巴利亚多利德的两家养老院中≤65 岁的人群。其中一组有 SARS-CoV-2 的既往感染史（n=68；69.4%），另一组无感染史（n=30；30.6%）。我们评估了 Comirnaty 疫苗的三剂接种反应和 5 次连续血清采样期间的抗体动态：接种前两剂后 2 次，第一次接种后 3 个月 1 次，6 个月时 1 次，第三次接种后 1 个月时 1 次。分析了针对 SARS-CoV-2 S1、RBD 和 N 抗原的 IgG 抗体。
两组人群针对 S1 和 RBD 的 Ab 水平均升高，但由于混合免疫（感染+疫苗接种），有既往感染史的经验组表现出 130 倍更高的体液免疫反应。对于 65 岁以下有既往感染史的人群，Comirnaty 对 COVID-19 的疫苗接种反应高于无感染史的人群。然而，S1 和 RBD 的抗体量在 6 个月时达到平衡。接种第三剂后，两组人群均提高了抗体数量，达到相似水平。两组人群的 N 抗体分析均提示再感染频繁。
第三剂对老年人有明显的益处，在接种前两剂六个月后抗体水平下降后，加强了抗体水平。
