Direction des maladies infectieuses - Unité infections respiratoires et vaccination, Santé publique France, 12 rue du Val d'Osne, Saint-Maurice 94415, France.
Sully Group, 3 av. Doyen Louis Weil, Grenoble 38000, France.
Vaccine. 2023 Mar 24;41(13):2280-2288. doi: 10.1016/j.vaccine.2023.02.062. Epub 2023 Feb 27.
The emergence of SARS-CoV-2 variants calls for continuous monitoring of vaccine effectiveness (VE). We estimated the absolute effectiveness of complete 2-dose primary vaccination and booster vaccination with COVID-19 mRNA vaccines, and the duration of protection against Delta and Omicron BA.1 symptomatic infection and severe outcomes. French residents aged ≥50 years, who presented with SARS-CoV-2-like symptoms and tested for SARS-CoV-2 between June 6, 2021 and February 10, 2022 were included. A test-negative study was conducted to estimate VE against symptomatic infection, using conditional logistic regression models. Cox proportional hazard regressions were performed to assess additional protection against severe COVID-19 outcomes (any hospitalization, and intensive care units [ICU] admission or in-hospital death). In total, 273732 cases and 735 919 controls were included. VE against symptomatic infection after 2-doses vaccination was 86% (95% CI: 75-92%) for Delta and 70% (58-79%) for Omicron, 7-30 days post vaccination. Protection waned over time, reaching 60% (57-63%) against Delta and 20% (16.-24%) for Omicron BA.1 > 120 days after vaccination. The booster dose fully restored protection against symtpomatic Delta infection (95% [81-99%]) but only partially against symptomatic Omicron BA.1 infection (63% [59-67%]). VE against Delta-related severe outcomes was above 95% with 2 doses, and persisted for at least four months. Protection against any Omicron BA.1-hospitalization was 92% (65%-99%) at 8-30 days, and 82% (67%-91%) > 120 days from the second dose. Against BA.1 ICU admission or in-patient death, VE stood at 98% (0-100%) at 8-30 days, and was 90% (40-99%) > 120 days from the second dose. Protection confered by mRNA vaccines against severe disease caused by either Delta or Omicron BA.1 appeared high and sustained over time. Protection against symptomatic diseases after 2 doses decreased rapidly, especially against Omicron BA.1. A booster dose restored high protection against Delta but only a partial one against Omicron BA.1.
SARS-CoV-2 变体的出现需要不断监测疫苗的有效性（VE）。我们评估了 COVID-19 mRNA 疫苗进行完全 2 剂初级接种和加强接种的绝对有效性，以及预防 Delta 和 Omicron BA.1 有症状感染和严重结果的保护持续时间。纳入年龄≥50 岁的法国居民，他们在 2021 年 6 月 6 日至 2022 年 2 月 10 日期间出现 SARS-CoV-2 样症状并接受 SARS-CoV-2 检测。使用条件逻辑回归模型进行了阴性检测研究，以估计针对有症状感染的 VE。采用 Cox 比例风险回归评估针对严重 COVID-19 结局（任何住院、重症监护病房 [ICU] 入院或住院死亡）的额外保护作用。共纳入 273732 例病例和 735919 例对照。接种 2 剂疫苗后，针对 Delta 的有效性为 86%（95%CI：75-92%），针对 Omicron 的有效性为 70%（58-79%），在接种后 7-30 天。随着时间的推移，保护作用减弱，接种后 60%（57-63%）针对 Delta，20%（16.-24%）针对 Omicron BA.1>120 天。加强针完全恢复了对 Delta 有症状感染的保护作用（95%[81-99%]），但仅部分恢复了对 Omicron BA.1 有症状感染的保护作用（63%[59-67%]）。接种 2 剂疫苗对 Delta 相关严重结局的 VE 超过 95%，至少持续 4 个月。接种后 8-30 天内，针对任何 Omicron BA.1-住院的保护作用为 92%（65%-99%），接种后>120 天的保护作用为 82%（67%-91%）。针对 BA.1 ICU 入院或住院死亡，接种后 8-30 天的 VE 为 98%（0-100%），接种后>120 天的 VE 为 90%（40-99%）。mRNA 疫苗对 Delta 或 Omicron BA.1 引起的严重疾病的保护作用似乎很高且随着时间的推移而持续。接种 2 剂疫苗后，针对有症状疾病的保护作用迅速下降，尤其是针对 Omicron BA.1。加强针恢复了对 Delta 的高保护作用，但仅对 Omicron BA.1 恢复了部分保护作用。
