tetano
Editor, Senior Moderator
Int J Infect Dis
. 2024 Aug 7:107202.
doi: 10.1016/j.ijid.2024.107202. Online ahead of print. Influenza epidemiology and vaccine effectiveness during the 2023/2024 season in Italy: A test-negative case-control study
Alexander Domnich[SUP] 1 [/SUP], Giancarlo Icardi[SUP] 2 [/SUP], Donatella Panatto[SUP] 3 [/SUP], Marianna Scarpaleggia[SUP] 4 [/SUP], Carlo-Simone Trombetta[SUP] 4 [/SUP], Matilde Ogliastro[SUP] 4 [/SUP], Federica Stefanelli[SUP] 5 [/SUP], Bianca Bruzzone[SUP] 5 [/SUP], Andrea Orsi[SUP] 2 [/SUP]
Affiliations
Objectives: In order to support policymakers in allocating resources, we aimed to assess vaccine effectiveness (VE) of inactivated influenza vaccines (IIVs) available for Italian adults in the 2023/2024 season.
Methods: A hospital-based test-negative case-control study was conducted in Genoa between mid-October 2023 and mid-April 2024. Adult (≥18 years) inpatients with prescription of a polymerase chain reaction test for influenza were eligible.
Results: Of 1,664 adults analyzed, most (82%) of which were ≥65 years, 114 (6.9%) tested positive for influenza A. Most (92%) cases were caused by subclades 6B.1A.5a.2a and 6B.1A.5a.2a.1 of the A(H1N1)pdm09 subtype. In older adults aged ≥65 years vaccination was effective at 51% (95% CI: 8%, 74%) against any influenza A and 49% (95% CI: 2%, 73%) against A(H1N1)pdm09. Compared with non-vaccinated older adults, VE point estimates for the adjuvanted and, especially, high-dose IIVs were higher than those for the standard-dose non-adjuvanted IIV.
Conclusion: The 2023/2024 seasonal influenza vaccination proved moderately effective in preventing hospitalization for laboratory-confirmed influenza. Being more appropriate for older adults, local policymakers and vaccinating physicians should maximize adoption of the enhanced IIVs.
Keywords: Influenza; adjuvanted influenza vaccine; adults; high-dose influenza vaccine; influenza vaccine; vaccine effectiveness.
. 2024 Aug 7:107202.
doi: 10.1016/j.ijid.2024.107202. Online ahead of print. Influenza epidemiology and vaccine effectiveness during the 2023/2024 season in Italy: A test-negative case-control study
Alexander Domnich[SUP] 1 [/SUP], Giancarlo Icardi[SUP] 2 [/SUP], Donatella Panatto[SUP] 3 [/SUP], Marianna Scarpaleggia[SUP] 4 [/SUP], Carlo-Simone Trombetta[SUP] 4 [/SUP], Matilde Ogliastro[SUP] 4 [/SUP], Federica Stefanelli[SUP] 5 [/SUP], Bianca Bruzzone[SUP] 5 [/SUP], Andrea Orsi[SUP] 2 [/SUP]
Affiliations
- PMID: 39122207
- DOI: 10.1016/j.ijid.2024.107202
Objectives: In order to support policymakers in allocating resources, we aimed to assess vaccine effectiveness (VE) of inactivated influenza vaccines (IIVs) available for Italian adults in the 2023/2024 season.
Methods: A hospital-based test-negative case-control study was conducted in Genoa between mid-October 2023 and mid-April 2024. Adult (≥18 years) inpatients with prescription of a polymerase chain reaction test for influenza were eligible.
Results: Of 1,664 adults analyzed, most (82%) of which were ≥65 years, 114 (6.9%) tested positive for influenza A. Most (92%) cases were caused by subclades 6B.1A.5a.2a and 6B.1A.5a.2a.1 of the A(H1N1)pdm09 subtype. In older adults aged ≥65 years vaccination was effective at 51% (95% CI: 8%, 74%) against any influenza A and 49% (95% CI: 2%, 73%) against A(H1N1)pdm09. Compared with non-vaccinated older adults, VE point estimates for the adjuvanted and, especially, high-dose IIVs were higher than those for the standard-dose non-adjuvanted IIV.
Conclusion: The 2023/2024 seasonal influenza vaccination proved moderately effective in preventing hospitalization for laboratory-confirmed influenza. Being more appropriate for older adults, local policymakers and vaccinating physicians should maximize adoption of the enhanced IIVs.
Keywords: Influenza; adjuvanted influenza vaccine; adults; high-dose influenza vaccine; influenza vaccine; vaccine effectiveness.