Relative effectiveness of bivalent Original/Omicron BA.4-5 mRNA vaccine in preventing severe COVID-19 in persons 60 years and above during SARS-CoV-2 Omicron XBB.1.5 and other XBB sublineages circulation, Italy, April to June 2023

Massimo Fabiani; Alberto Mateo-Urdiales; Chiara Sacco; Maria Cristina Rota; Emmanouil Alexandros Fotakis; Daniele Petrone; Martina Del Manso; Andrea Siddu; Paola Stefanelli; Antonino Bella; Flavia Riccardo; Giovanni Rezza; Anna Teresa Palamara; Silvio Brusaferro; Patrizio Pezzotti; Italian Integrated Surveillance of COVID-19 study group and of the Italian COVID-19 Vaccines Registry group

doi:10.2807/1560-7917.ES.2023.28.32.2300397

Relative effectiveness of bivalent Original/Omicron BA.4-5 mRNA vaccine in preventing severe COVID-19 in persons 60 years and above during SARS-CoV-2 Omicron XBB.1.5 and other XBB sublineages circulation, Italy, April to June 2023

Euro Surveill. 2023 Aug;28(32):2300397. doi: 10.2807/1560-7917.ES.2023.28.32.2300397.

Authors

Massimo Fabiani¹, Alberto Mateo-Urdiales¹, Chiara Sacco¹, Maria Cristina Rota¹, Emmanouil Alexandros Fotakis^{2

1}, Daniele Petrone¹, Martina Del Manso¹, Andrea Siddu³, Paola Stefanelli¹, Antonino Bella¹, Flavia Riccardo¹, Giovanni Rezza³, Anna Teresa Palamara¹, Silvio Brusaferro⁴, Patrizio Pezzotti¹; Italian Integrated Surveillance of COVID-19 study group and of the Italian COVID-19 Vaccines Registry group⁵

Affiliations

¹ Department of Infectious Diseases, Istituto Superiore di Sanità, Rome, Italy.
² European Programme on Intervention Epidemiology Training (EPIET), European Centre for Disease Prevention and Control, Stockholm, Sweden.
³ General Directorate of Prevention, Italian Ministry of Health, Rome, Italy.
⁴ Office of the President, Istituto Superiore di Sanità, Rome, Italy.
⁵ Members of the author groups are listed under Acknowledgements.

PMID: 37561053
PMCID: PMC10416574
DOI: 10.2807/1560-7917.ES.2023.28.32.2300397

Abstract

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.

Keywords: COVID-19; Italy; Omicron XBB sublineages; bivalent mRNA vaccines; effectiveness.

MeSH terms

Aged
COVID-19 Vaccines* / administration & dosage
COVID-19* / prevention & control
Humans
Italy / epidemiology
Middle Aged
RNA, Messenger
SARS-CoV-2 / genetics
mRNA Vaccines

Substances

COVID-19 Vaccines
mRNA Vaccines
RNA, Messenger