ADULTS AGE 65 YEARS AND OLDER ARE DISPROPORTIONATELY AFFECTED BY THE FLU:
Older adults account for about 70%-85% of annual flu-related deaths in the United States.1
The severity of influenza varies from year to year, but it always brings more severe illness to older adults. For example, during 2022–2023, there were an estimated 130,368 to 468,051 flu-related hospitalizations among people 65 years or older in the United States.3 CDC’s preliminary estimate for the 2023-24 is 164,034 to 516,621 flu-related hospitalizations.4
Older adults experience longer hospital stays than younger adults.5 Older adults are at increased risk of further hospitalizations, transfer to hospice, or mortality after an influenza-associated hospitalization.5-6
SERIOUS COMPLICATIONS
Complications from influenza can lead to life-threatening conditions in older adults. Serious complications include the following7:
Those Living With Chronic Diseases
Influenza is particularly dangerous for adults living with chronic diseases, such as diabetes and heart and lung conditions. Many adults remain unaware that they have a chronic disease and ensuring that they get vaccinated provides a layer of protection for vulnerable patient populations.7-9
In recent influenza seasons, people with diabetes account for about 30% of adult flu hospitalizations.8
Patients with heart disease, or those who had a stroke, have a higher risk of developing serious complications. from influenza, including myocarditis, inflammation of muscle tissues, heart attack, and multi-organ failure.7,9-11
Patients with chronic obstructive pulmonary disease (COPD), asthma, or other lung conditions also have a higher risk of complications from influenza. Since people with these conditions have sensitive airways, inflammation caused by the flu can make COPD symptoms worse, trigger asthma attacks, and easily lead to the development of pneumonia and other respiratory diseases.6-7,9-11 Influenza infections have been frequently identified in persons with COPD exacerbation.
Immunosenescence is the biological aging process associated with progressive decline in systemic immunity. This gradual deterioration of the immune system, brought on by natural aging, can cause increased susceptibility to common infectious diseases, including influenza, among older adults.2,6,12-13
Additionally, inflamm-aging, a chronic progressive increase in the proinflammatory status of the older adult, contributes to all aging-related diseases and renders older adults more vulnerable to complications as a result of infection with influenza.14
Even when they recover from the flu, older adults may never fully regain their pre-influenza health, abilities, and lifestyle. Moreover, for months after getting the flu, older adults may still be at increased risk of cardiovascular problems, such as heart attack or stroke, due to lingering inflammation and an increased risk of blood clots associated with infections like influenza.9 Influenza vaccination has been associated with lower risk of acute cardiovascular events and stroke.1,9
EVIDENCE-BASED RESOURCES
From the Centers for Disease Control and Prevention
From the Literature
Immunize.org and Seqirus are not responsible for content found at external links.1. Centers for Disease Control and Prevention. Flu and people 65 years and older. https://www.cdc.gov/flu/highrisk/65over.htm. Accessed July 19, 2025. 2. National Foundation for Infectious Diseases. Call to action: Reinvigorating influenza prevention in US adults age 65 years and older. https://www.nfid.org/wp-content/uploads/2023/05/flu-65.pdf. Accessed July 19, 2025. 3. Centers for Disease Control and Prevention. Preliminary estimated flu disease burden, 2022–2023 flu season. https://www.cdc.gov/flu-burden/php/data-vis/2022-2023.html. Accessed July 19, 2025. 4. Centers for Disease Control and Prevention. Preliminary estimated flu disease burden, 2023–2024 flu season. https://www.cdc.gov/flu-burden/php/data-vis/2023-2024.html. Accessed July 19, 2025. 5. Centers for Disease Control and Prevention. This season’s flu vaccines reduced flu medical visits and hospitalizations across all ages. https://www.cdc.gov/flu/whats-new/2023-2024-vaccines-reduce-medical-visits.html. Accessed July 19, 2025. 6. Andrew MK, MacDonald S, Godin J, et al. Persistent functional decline following hospitalization with influenza or acute respiratory illness. J Am Geriatr Soc. 2021;69(3):696-703. doi:10.1111/jgs.16950. 7. Centers for Disease Control and Prevention. Signs and symptoms of flu. https://www.cdc.gov/flu/signs-symptoms/index.html. Accessed July 19, 2025. 8. Centers for Disease Control and Prevention. Flu and people with diabetes. https://www.cdc.gov/flu/highrisk/diabetes.html. Accessed July 19, 2025. 9. Centers for Disease Control and Prevention. Flu and people with heart disease or history of stroke. https://www.cdc.gov/flu/highrisk/heartdisease.htm. Accessed July 19, 2025. 10. Centers for Disease Control and Prevention. People at increased risk for flu complications. https://www.cdc.gov/flu/highrisk/index.htm. Accessed July 19, 2025. 11. Coleman BL, Fadel SA, Fitzpatrick T, et al. Risk factors for serious outcomes associated with influenza illness in high-versus low-and middle-income countries. Systematic literature review and meta-analysis. Influenza Other Respir Viruses. 2018;12(1):22-29. doi:10.1111/irv.12504. 12. Centers for Disease Control and Prevention. Key facts about seasonal flu vaccine. https://www.cdc.gov/flu/vaccines/keyfacts.html. Accessed July 19, 2025. 13. Dugan HL, Henry, C, Wilson PC. Aging and influenza vaccine-induced immunity. Cell Immunol. 2020:348:103998. doi:10.1016/j.cellimm.2019.103998. 14. Xia S, Zhang X, Zheng S, et al. An update on inflamm-aging: mechanisms, prevention, and treatment. J Immunol Research. 2016;2016:8426874. doi:10.1155/2016/8426874.