辉瑞-BioNTech 新冠疫苗在意大利北部伦巴第大区米兰医护人员中的免疫原性和有效性。

Immunogenicity and effectiveness of BNT162b2 COVID-19 vaccine in a cohort of healthcare workers in Milan (Lombardy Region, Northern Italy).

机构信息

Epidemiology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan (Italy);

These authors equally contributed to this paper.

出版信息

Epidemiol Prev. 2022 Jul-Aug;46(4):250-258. doi: 10.19191/EP22.4.A513.065.

DOI:10.19191/EP22.4.A513.065

PMID:36259341

Abstract

OBJECTIVES

to evaluate immunogenicity and effectiveness of BNT162b2 COVID-19 vaccine in a cohort of healthcare workers (HCWs).

DESIGN

cohort study.

SETTING AND PARTICIPANTS

in a hospital in Milan (Lombardy Region, Northern Italy) HCWs without ("negative cohort") and with ("positive cohort") history of SARS-CoV-2 infection or elevated serum antibody before the vaccination campaign (27.12.2020) were included. Data collection and follow-up covered the period 27.12.2020-13.05.2022.

MAIN OUTCOMES MEASURES

serum anti-spike-1 (anti-S1) antibody levels after vaccination; 2. vaccine effectiveness (VE) against SARS-CoV-2 infections (either symptomatic or not) in the negative cohort. Data on infections were extracted from multiple sources (laboratory, accident reports, questionnaires). Vaccination was treated as a time-dependent variable. Using unvaccinated person-time as reference, hazard ratios (HR) of infections and 95% confidence intervals (95%CI) were calculated with a Cox regression model adjusted for gender, age, and occupation. VE was calculated as (1 - HR)×100.

RESULTS

5,596 HCWs were included, 4,771 in the negative and 825 in the positive cohort. In both cohorts, serum anti-S1 antibodies were high one months after the second dose, halved after six months, and returned to high levels after the third dose. In the negative cohort, 1,401 SARS-CoV-2 infections were identified. VE was 70% (95%CI 54-80; 46 infected) in the first four months after the second dose and later declined to 16% (95%CI 0-43; 97 infected). After the third dose, VE increased to 57% (95%CI 35-71; 61 infected) in the first month but rapidly declined over time, particularly after three months (24% in the fourth month and 1% afterwards). The number of infections avoided by vaccination was estimated to be 643 (95%CI 236-1,237).

CONCLUSIONS

in spite of rapidly declining effectiveness, vaccination helped to avoid several hundred infections in the considered hospital.

摘要

目的

评估 BNT162b2 COVID-19 疫苗在医护人员（HCWs）队列中的免疫原性和有效性。

设计

队列研究。

地点和参与者

在米兰的一家医院（意大利北部伦巴第大区），纳入了在疫苗接种运动前（2020 年 12 月 27 日）没有（“阴性队列”）和有（“阳性队列”）SARS-CoV-2 感染史或血清抗体升高的 HCWs。数据收集和随访覆盖了 2020 年 12 月 27 日至 2022 年 5 月 13 日的时间段。

主要结局指标

接种疫苗后血清抗刺突蛋白-1（抗-S1）抗体水平；2. 阴性队列中针对 SARS-CoV-2 感染（无论症状或无症状）的疫苗有效性（VE）。感染数据来自多个来源（实验室、事故报告、问卷调查）。将疫苗接种作为时间依赖性变量。使用未接种人员的时间作为参考，使用 Cox 回归模型调整性别、年龄和职业，计算感染的风险比（HR）和 95%置信区间（95%CI）。VE 计算为（1 - HR）×100。

结果

共纳入 5596 名 HCWs，其中 4771 名在阴性队列，825 名在阳性队列。在两个队列中，第二次接种后一个月血清抗-S1 抗体水平较高，六个月后减半，第三次接种后又恢复到高水平。在阴性队列中，共发现 1401 例 SARS-CoV-2 感染。第二次接种后四个月 VE 为 70%（95%CI 54-80；46 例感染），随后下降至 16%（95%CI 0-43；97 例感染）。第三次接种后，第一个月 VE 增加至 57%（95%CI 35-71；61 例感染），但随着时间的推移迅速下降，尤其是在三个月后（第四个月 24%，之后为 1%）。估计接种疫苗可避免 643 例（95%CI 236-1237）感染。