Introduction:
This study aimed to evaluate the long-term effectiveness of COVID-19 vaccination in healthcare workers by analyzing the population’s response to the vaccine after two years, based on anti-SARS-CoV-2 protein S antibody levels. Additionally, the study aimed to assess the impact of basic factors on antibody levels.

Material and methods:
A total of 4,090 healthcare workers were included in the study, and their antibody levels were measured using ELISA to detect anti-SARS-CoV-2 immunoglobulin G (IgG). Statistical analysis was conducted to examine the influence of COVID-19 infection, vaccination status, and number of vaccine doses on antibody concentrations.

Results and Conclusion:
The majority of participants (85.1%) received the Pfizer/BioNTech vaccine, while a smaller percentage chose vector vaccines such as AstraZeneca and Johnson & Johnson. The incidence of COVID-19 among vaccinated individuals was relatively low for all vaccines, confirming their effectiveness in preventing symptomatic SARS-CoV-2 infection. The study observed variations in IgG antibody levels within the study population, with only 0.46% of individuals testing negative for the presence of antibodies. The average anti-SARS-CoV-2 IgG values showed significant differences across consecutive 3-month periods following infection or vaccination, with a gradual decrease over time. Notably, the most significant changes in antibody levels were observed within the first 6 months (mean values ranged from 3647.11 BAU/ml to 2601.49 BAU/ml). Subsequently, minor fluctuations were observed, with mean antibody values hovering around 2000 BAU/ml. The differences between average anti-SARS-CoV-2 IgG values between consecutive 3-month periods from disease onset were statistically significant.



中文翻译：

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医护人员接种 COVID-19 疫苗：长期效益和保护

简介：
本研究旨在通过根据抗 SARS-CoV-2 蛋白 S 抗体水平分析人群两年后对疫苗的反应，评估医护人员接种 COVID-19 疫苗的长期有效性。此外，该研究旨在评估基本因素对抗体水平的影响。

材料和方法：
该研究共纳入了 4,090 名医护人员，使用 ELISA 检测他们的抗体水平，以检测抗 SARS-CoV-2 免疫球蛋白 G (IgG)。进行统计分析以检查 COVID-19 感染、疫苗接种状况和疫苗剂量数对抗体浓度的影响。

结果与结论：
大多数参与者（85.1%）接种了辉瑞/BioNTech 疫苗，少数人选择了阿斯利康和强生等载体疫苗。对于所有疫苗而言，接种疫苗的个体中 COVID-19 的发病率相对较低，这证实了它们在预防有症状的 SARS-CoV-2 感染方面的有效性。该研究观察到研究人群中 IgG 抗体水平存在差异，只有 0.46% 的人抗体检测结果呈阴性。感染或接种疫苗后连续 3 个月的平均抗 SARS-CoV-2 IgG 值显示出显着差异，并随着时间的推移逐渐下降。值得注意的是，抗体水平最显着的变化是在前 6 个月内观察到的（平均值范围为 3647.11 BAU/ml 至 2601.49 BAU/ml）。随后，观察到轻微波动，平均抗体值徘徊在 2000 BAU/ml 左右。发病后连续 3 个月期间的平均抗 SARS-CoV-2 IgG 值之间的差异具有统计学意义。