부산대학교 도서관

Summary Background The omicron (B.1.1.529) variant of SARS-CoV-2 has increased capacity to elude immunity and cause breakthrough infections. The aim of this study was to estimate the effectiveness of mRNA-based vaccine boosters (third dose) against infection with the omicron variant by age, sex, time since complete vaccination, type of primary vaccine, and type of booster. Methods In this nationwide cohort study, we linked data from three nationwide population registries in Spain (Vaccination Registry, Laboratory Results Registry, and National Health System registry) to select community-dwelling individuals aged 40 years or older, who completed their primary vaccine schedule at least 3 months before the start of follow-up, and had not tested positive for SARS-CoV-2 since the start of the pandemic. On each day between Jan 3, and Feb 6, 2022, we matched individuals who received a booster mRNA vaccine and controls of the same sex, age group, postal code, type of vaccine, time since primary vaccination, and number of previous tests. We estimated risk of laboratory-confirmed SARS-CoV-2 infection using the Kaplan-Meier method and compared groups using risk ratios (RR) and risk differences. Vaccine effectiveness was calculated as one minus RR. Findings Between Jan 3, and Feb 6, 2022, 3 111 159 matched pairs were included in our study. Overall, the estimated effectiveness from day 7 to 34 after a booster was 51*3% (95% CI 50*2--52*4). Estimated effectiveness was 52*5% (51*3--53*7) for an mRNA-1273 booster and 46*2% (43*5--48*7) for a BNT162b2 booster. Effectiveness was 58*6% (55*5--61*6) if primary vaccination had been with ChAdOx1 nCoV-19 (Oxford--AstraZeneca), 55*3% (52*3--58*2) with mRNA-1273 (Moderna), 49*7% (48*3--51*1) with BNT162b2 (Pfizer--BioNTech), and 48*0% (42*5--53*7) with Ad26.COV2.S (Janssen). Estimated effectiveness was 43*6% (40*0--47*1) when the booster was administered between 151 days and 180 days after complete vaccination and 52*2% (51*0--53*3) if administered more than 180 days after primary scheduled completion. Interpretation Booster mRNA vaccine-doses were moderately effective in preventing infection with the omicron variant of SARS-CoV-2 for over a month after administration, which indicates their suitability as a strategy to limit the health effects of COVID-19 in periods of omicron variant domination. Estimated effectiveness was higher for mRNA-1273 compared with BNT162b2 and increased with time between completed primary vaccination and booster. Funding None. Author Affiliation: (a) Department of Communicable Diseases, National Centre of Epidemiology, Institute of Health Carlos III, Madrid, Spain (b) Centro de Investigación Biomédica en Red (CIBER) on Infectious Diseases, Madrid, Spain (c) CIBER on Epidemiology and Public Health, Madrid, Spain (d) National Distance Education University, Madrid, Spain (e) Vaccines Division, General Directorate of Public Health, Ministry of Health, Madrid, Spain (f) Centre for the Coordination of Heath Alerts and Emergencies, General Directorate of Public Health, Ministry of Health, Madrid, Spain (g) Spanish Agency of Medicines and Medical Devices, Madrid, Spain (h) CAUSALab and Departments of Epidemiology and Biostatistics, Harvard T H Chan School of Public Health, Boston, MA, USA * Correspondence to: Dr Susana Monge, Department of Communicable Diseases, National Centre of Epidemiology, Institute of Health Carlos III, 28029 Madrid, Spain Byline: Susana Monge, PhD [smonge@isciii.es] (a,b), Ayelén Rojas-Benedicto, MSc (a,c,d), Carmen Olmedo, PhD (e), Clara Mazagatos, MSc (a,c), María José Sierra, PhD (f), Aurora Limia, PhD (e), Elisa Martín-Merino, PhD (g), Amparo Larrauri, PhD (a,c), Prof Miguel A Hernán, MD (h), David Moreno, Manuel Méndez Díaz, Ismael Huerta González, Antònia Galmés Truyols, Ana Barreno Estévez, Valvanuz García Velasco, Mª Jesús Rodríguez Recio, José Sacristán, Montserrat Martínez Marcos, Eliseo Pastor Villalba, María José Macías Ortiz, Ana García Vallejo, Amaya Sánchez Gómez, Rocío García Pina, Aurelio Barricarte Gurea, Rosa Sancho Martínez, Eva María Ochoa, Mauricio Vázquez Cantero, Atanasio Gómez Anés, María Jesús Pareja Megía, Yolanda Castán, Manuel Roberto Fonseca Álvarez, Antonia Salvà Fiol, Hilda Sánchez Janáriz, Luz López Arce, María Ángeles Cisneros Martín, Frederic Jose Gibernau, Cesar Fernandez Buey, Katja Villatoro Bongiorno, Francisco Javier Rubio García, Fernando Santos Guerra, Jenaro Astray Mochales, Francisco Javier Francisco Verdu, Isabel García Romero, Rosa Oriza Bernal, Tomás Gómez Pérez, Salomé Hijano Villegas, Sergio Román Soto, Diana Gómez-Barroso, María Fé Lapeña, Virgilio Yagüe Galaup, Mercedes Alfaro Latorre, Marta Aguilera Guzmán, Belén Crespo Sánchez-Eznarriaga, Montserrat Neira León, Noemí Cívicos Villa