Epidemiology Unit, Preventive Medicine Service, Dr. Balmis General University Hospital, Alicante Institute for Health and Biomedical Research (ISABIAL), Alicante, Spain.
Epidemiology Unit, Preventive Medicine Service, Dr. Balmis General University Hospital, Alicante Institute for Health and Biomedical Research (ISABIAL), Alicante, Spain; Preventive Medicine and Public Health Area, Faculty of Health Sciences, University of Alicante, Alicante, Spain.
Vaccine. 2024 Jul 25;42(19):4011-4021. doi: 10.1016/j.vaccine.2024.05.011. Epub 2024 May 17.
This study aimed to evaluate the effectiveness of SARS-CoV-2 mRNA vaccines in preventing infection and hospitalization among healthcare workers (HCWs) in the Valencian Community (Spain), considering vaccination timing, dose number, and predominant variant.
A test-negative case-control design estimated vaccine effectiveness against symptomatic disease and hospitalization due to SARS-CoV-2. HCWs who underwent PCR or antigen testing for SARS-CoV-2 from January 2021 to March 2022 were included. Cases had a positive diagnostic test, while controls had negative tests. Adjusted vaccine effectiveness (aVE) was calculated using the formula: aVE = (1 - Odds ratio) × 100.
During the Delta variant's predominance, aVE against infection within 12-120 days post-second dose was 64.8 % (BNT162b2) and 59.4 % (mRNA-1273), declining to 21.2 % and 42.2 %, respectively, after 120 days. For the Omicron variant, aVE within 12-120 days post-second dose was 61.1 % (BNT162b2) and 85.1 % (mRNA-1273), decreasing to 36.7 % and 24.9 %, respectively, after 120 days. After a booster dose of mRNA-1273, aVE was 64.0 % (BNT162b2 recipients) and 65.9 % (initial mRNA-1273 recipients). Regardless of variant, aVE for hospitalization prevention after 2 doses was 87.0 % (BNT162b2) and 89.0 % (mRNA-1273).
The administration of two doses of Moderna-mRNA-1273 against SARS-CoV-2 in HCWs proved to be highly effective in preventing infections and hospitalizations in the first 120 days after the second dose during the predominance of the Omicron variant. The decline in VE after 120 days since the administration of the second dose was significantly restored by the booster dose administration. This increase in VE was greater for the Pfizer vaccine. COVID-19 hospitalization prevention remained stable with both mRNA vaccines throughout the study period.
本研究旨在评估 SARS-CoV-2 mRNA 疫苗在西班牙巴伦西亚社区（Valencian Community）预防医护人员（HCWs）感染和住院的效果，同时考虑疫苗接种时间、剂量数和主要变异株。
采用病例对照研究设计，评估了针对 SARS-CoV-2 的症状性疾病和住院治疗的疫苗有效性。研究对象为 2021 年 1 月至 2022 年 3 月期间接受 SARS-CoV-2 PCR 或抗原检测的 HCWs。病例组的诊断性检测呈阳性，对照组的检测结果呈阴性。使用公式计算调整后的疫苗有效性（aVE）：aVE = (1 - 比值比) × 100。
在 Delta 变异株流行期间，接种第二剂后 12-120 天内，mRNA-1273 和 BNT162b2 对感染的 aVE 分别为 64.8%和 59.4%，120 天后分别降至 21.2%和 42.2%。对于 Omicron 变异株，mRNA-1273 和 BNT162b2 在接种第二剂后 12-120 天内的 aVE 分别为 61.1%和 85.1%，120 天后分别降至 36.7%和 24.9%。接种 mRNA-1273 加强针后，aVE 分别为 64.0%（BNT162b2 接种者）和 65.9%（初始 mRNA-1273 接种者）。无论变异株如何，接种两剂疫苗对住院预防的 aVE 均为 87.0%（BNT162b2）和 89.0%（mRNA-1273）。
在 Omicron 变异株流行期间，HCWs 接种两剂 Moderna-mRNA-1273 疫苗对预防感染和住院非常有效，在接种第二剂后的 120 天内效果显著。第二剂接种后 120 天内疫苗有效性的下降，通过加强针接种显著恢复。对于 Pfizer 疫苗，这种疫苗有效性的增加更为显著。在整个研究期间，两种 mRNA 疫苗对 COVID-19 住院预防的效果均保持稳定。
