Marra Alexandre R, Miraglia João Luiz, Malheiro Daniel Tavares, Guozhang Yang, Teich Vanessa Damazio, Victor Elivane da Silva, Pinho João Renato Rebello, Cypriano Adriana, Vieira Laura Wanderly, Polonio Miria, Ornelas Rafael Herrera, de Oliveira Solange Miranda, Borges Flavio Araujo, Oler Silvia Cristina Cassiano, Ricardo Victória Catharina Volpe, Maezato Aline Miho, Callado Gustavo Yano, Schettino Guilherme de Paula Pinto, de Oliveira Ketti Gleyzer, Santana Rúbia Anita Ferraz, Malta Fernanda de Mello, Amgarten Deyvid, Boechat Ana Laura, Kobayashi Takaaki, Salinas Jorge L, Edmond Michael B, Rizzo Luiz Vicente
Hospital Israelita Albert Einstein, São Paulo, Brazil.
Department of Internal Medicine, University of Iowa, Iowa City, Iowa, United States.
Antimicrob Steward Healthc Epidemiol. 2023 Jun 22;3(1):e104. doi: 10.1017/ash.2023.173. eCollection 2023.
To compare the long-term vaccine effectiveness between those receiving viral vector [Oxford-AstraZeneca (ChAdOx1)] or inactivated viral (CoronaVac) primary series (2 doses) and those who received an mRNA booster (Pfizer/BioNTech) (the third dose) among healthcare workers (HCWs).
We conducted a retrospective cohort study among HCWs (aged ≥18 years) in Brazil from January 2021 to July 2022. To assess the variation in the effectiveness of booster dose over time, we estimated the effectiveness rate by taking the log risk ratio as a function of time.
Of 14,532 HCWs, coronavirus disease 2019 (COVID-19) was confirmed in 56.3% of HCWs receiving 2 doses of CoronaVac vaccine versus 23.2% of HCWs receiving 2 doses of CoronaVac vaccine with mRNA booster ( < .001), and 37.1% of HCWs receiving 2 doses of ChAdOx1 vaccine versus 22.7% among HCWs receiving 2 doses of ChAdOx1 vaccine with mRNA booster ( < .001). The highest vaccine effectiveness with mRNA booster was observed 30 days after vaccination: 91% for the CoronaVac vaccine group and 97% for the ChAdOx1 vaccine group. Vacine effectiveness declined to 55% and 67%, respectively, at 180 days. Of 430 samples screened for mutations, 49.5% were SARS-CoV-2 delta variants and 34.2% were SARS-CoV-2 omicron variants.
Heterologous COVID-19 vaccines were effective for up to 180 days in preventing COVID-19 in the SARS-CoV-2 delta and omicron variant eras, which suggests the need for a second booster.
比较医护人员中接受病毒载体疫苗[牛津-阿斯利康（ChAdOx1）]或灭活病毒疫苗（科兴疫苗）基础免疫系列（2剂）的人群与接受mRNA加强针（辉瑞/生物科技）（第3剂）的人群之间的长期疫苗效力。
我们于2021年1月至2022年7月在巴西对年龄≥18岁的医护人员开展了一项回顾性队列研究。为评估加强针效力随时间的变化，我们将对数风险比作为时间的函数来估计效力率。
在14532名医护人员中，2剂科兴疫苗接种者中有56.3%确诊感染2019冠状病毒病（COVID-19），而接种2剂科兴疫苗并接种mRNA加强针的医护人员中这一比例为23.2%（P<0.001）；2剂ChAdOx1疫苗接种者中有37.1%确诊感染COVID-19，而接种2剂ChAdOx1疫苗并接种mRNA加强针的医护人员中这一比例为22.7%（P<0.001）。接种mRNA加强针后30天观察到最高疫苗效力：科兴疫苗组为91%，ChAdOx1疫苗组为97%。180天时疫苗效力分别降至55%和67%。在筛查的430份样本中，49.5%为严重急性呼吸综合征冠状病毒2（SARS-CoV-2）德尔塔变异株，34.2%为SARS-CoV-2奥密克戎变异株。
在SARS-CoV-2德尔塔和奥密克戎变异株流行时代，异源COVID-19疫苗在长达180天的时间里对预防COVID-19有效，这表明需要接种第二剂加强针。
