tetano
Editor, Senior Moderator
Adv Ther
. 2023 Feb 15.
doi: 10.1007/s12325-023-02432-1. Online ahead of print.
High Clinical Burden of Influenza Disease in Adults Aged ≥ 65 Years: Can We Do Better? A Systematic Literature Review
Jakob Langer[SUP] 1 [/SUP], Verna L Welch[SUP] 2 [/SUP], Mary M Moran[SUP] 2 [/SUP], Alejandro Cane[SUP] 2 [/SUP], Santiago M C Lopez[SUP] 2 [/SUP], Amit Srivastava[SUP] 3 [/SUP], Ashley L Enstone[SUP] 4 [/SUP], Amy Sears[SUP] 4 [/SUP], Kristen J Markus[SUP] 4 [/SUP], Maria Heuser[SUP] 4 [/SUP], Rachel M Kewley[SUP] 4 [/SUP], Isabelle J Whittle[SUP] 4 [/SUP]
Affiliations
Abstract
Introduction: Influenza is a respiratory infection associated with a significant clinical burden globally. Adults aged ≥ 65 years are at increased risk of severe influenza-related symptoms and complications due to chronic comorbidity and immunosenescence. Annual influenza vaccination is recommended; however, current influenza vaccines confer suboptimal protection, in part due to antigen mismatch and poor durability. This systematic literature review characterizes the global clinical burden of seasonal influenza among adults aged ≥ 65 years.
Methods: An electronic database search was conducted and supplemented with a conference abstract search. Included studies described clinical outcomes in the ≥ 65 years population across several global regions and were published in English between January 1, 2012 and February 9, 2022.
Results: Ninety-nine publications were included (accounting for > 156,198,287 total participants globally). Clinical burden was evident across regions, with most studies conducted in the USA and Europe. Risk of influenza-associated hospitalization increased with age, particularly in those aged ≥ 65 years living in long-term care facilities, with underlying comorbidities, and infected with A(H3N2) strains. Seasons dominated by circulating A(H3N2) strains saw increased risk of influenza-associated hospitalization, intensive care unit admission, and mortality within the ≥ 65 years population. Seasonal differences in clinical burden were linked to differences in circulating strains.
Conclusions: Influenza exerts a considerable burden on adults aged ≥ 65 years and healthcare systems, with high incidence of hospitalization and mortality. Substantial influenza-associated clinical burden persists despite increasing vaccination coverage among adults aged ≥ 65 years across regions included in this review, which suggests limited effectiveness of currently available seasonal influenza vaccines. To reduce influenza-associated clinical burden, influenza vaccine effectiveness must be improved. Next generation vaccine production using mRNA technology has demonstrated high effectiveness against another respiratory virus-SARS-CoV-2-and may overcome the practical limitations associated with traditional influenza vaccine production.
Keywords: Burden of disease; Hospitalization; Mortality; Older adults; Strain; Vaccination; mRNA vaccine.
. 2023 Feb 15.
doi: 10.1007/s12325-023-02432-1. Online ahead of print.
High Clinical Burden of Influenza Disease in Adults Aged ≥ 65 Years: Can We Do Better? A Systematic Literature Review
Jakob Langer[SUP] 1 [/SUP], Verna L Welch[SUP] 2 [/SUP], Mary M Moran[SUP] 2 [/SUP], Alejandro Cane[SUP] 2 [/SUP], Santiago M C Lopez[SUP] 2 [/SUP], Amit Srivastava[SUP] 3 [/SUP], Ashley L Enstone[SUP] 4 [/SUP], Amy Sears[SUP] 4 [/SUP], Kristen J Markus[SUP] 4 [/SUP], Maria Heuser[SUP] 4 [/SUP], Rachel M Kewley[SUP] 4 [/SUP], Isabelle J Whittle[SUP] 4 [/SUP]
Affiliations
- PMID: 36790682
- DOI: 10.1007/s12325-023-02432-1
Abstract
Introduction: Influenza is a respiratory infection associated with a significant clinical burden globally. Adults aged ≥ 65 years are at increased risk of severe influenza-related symptoms and complications due to chronic comorbidity and immunosenescence. Annual influenza vaccination is recommended; however, current influenza vaccines confer suboptimal protection, in part due to antigen mismatch and poor durability. This systematic literature review characterizes the global clinical burden of seasonal influenza among adults aged ≥ 65 years.
Methods: An electronic database search was conducted and supplemented with a conference abstract search. Included studies described clinical outcomes in the ≥ 65 years population across several global regions and were published in English between January 1, 2012 and February 9, 2022.
Results: Ninety-nine publications were included (accounting for > 156,198,287 total participants globally). Clinical burden was evident across regions, with most studies conducted in the USA and Europe. Risk of influenza-associated hospitalization increased with age, particularly in those aged ≥ 65 years living in long-term care facilities, with underlying comorbidities, and infected with A(H3N2) strains. Seasons dominated by circulating A(H3N2) strains saw increased risk of influenza-associated hospitalization, intensive care unit admission, and mortality within the ≥ 65 years population. Seasonal differences in clinical burden were linked to differences in circulating strains.
Conclusions: Influenza exerts a considerable burden on adults aged ≥ 65 years and healthcare systems, with high incidence of hospitalization and mortality. Substantial influenza-associated clinical burden persists despite increasing vaccination coverage among adults aged ≥ 65 years across regions included in this review, which suggests limited effectiveness of currently available seasonal influenza vaccines. To reduce influenza-associated clinical burden, influenza vaccine effectiveness must be improved. Next generation vaccine production using mRNA technology has demonstrated high effectiveness against another respiratory virus-SARS-CoV-2-and may overcome the practical limitations associated with traditional influenza vaccine production.
Keywords: Burden of disease; Hospitalization; Mortality; Older adults; Strain; Vaccination; mRNA vaccine.