Eurosurv. Relative effectiveness of bivalent Original/Omicron BA.4-5 mRNA vaccine in preventing severe COVID-19 in persons 60 years and above during S

[tetano]

• Massimo Fabiani[SUP]1[/SUP] , Alberto Mateo-Urdiales[SUP]1[/SUP] , Chiara Sacco[SUP]1[/SUP] , Maria Cristina Rota[SUP]1[/SUP] , Emmanouil Alexandros Fotakis[SUP]1,2[/SUP] , Daniele Petrone[SUP]1[/SUP] , Martina Del Manso[SUP]1[/SUP] , Andrea Siddu[SUP]3[/SUP] , Paola Stefanelli[SUP]1[/SUP] , Antonino Bella[SUP]1[/SUP] , Flavia Riccardo[SUP]1[/SUP] , Giovanni Rezza[SUP]3[/SUP] , Anna Teresa Palamara[SUP]1[/SUP] , Silvio Brusaferro[SUP]4[/SUP] , Patrizio Pezzotti[SUP]1[/SUP] , on behalf of the Italian Integrated Surveillance of COVID-19 study group and of the Italian COVID-19 Vaccines Registry group[SUP]5[/SUP]

​During predominant circulation of SARS-CoV-2 Omicron XBB.1.5 and other XBB sublineages (April–June 2023), we found that a second or third booster of Comirnaty bivalent Original/Omicron BA.4-5 mRNA vaccine, versus a first booster received at least 120 days earlier, was effective in preventing severe COVID-19 for more than 6 months post-administration in persons 60 years and above. In view of autumn 2023 vaccination campaigns, use of bivalent Original/Omicron BA.4-5 mRNA vaccines might be warranted until monovalent COVID-19 vaccines targeting Omicron XBB.1 sublineages become available.

https://www.eurosurveillance.org/content/10.2807/1560-7917.ES.2023.28.32.2300397