Market scope note: This article draws on sources from both Korea and the United States. Each piece of information is labeled 🇰🇷 Korea or 🇺🇸 U.S. in the text to indicate which country it applies to.
Many families have watched a parent struggle through even a mild cold for weeks, or seen a single bout of flu lead to hospitalization. This is not simply a matter of declining stamina. As we age, the immune system undergoes structural changes. The medical community calls this process 'immunosenescence.' The thymus shrinks, production of new immune cells decreases, and a state of low-grade chronic inflammation known as 'inflammaging' develops in parallel. The result is reduced resistance to infection and a greater tendency for infections to escalate into serious illness.
🇰🇷 Korea According to Statistics Korea's 2024 Cause-of-Death Statistics, the three leading causes of death in Korea in 2024 were cancer, heart disease, and pneumonia, which together accounted for 42.6% of all deaths. Pneumonia in particular continues to rise even as mortality from cancer and cerebrovascular disease gradually declines, a trend closely linked to population aging. A big-data analysis by a research team at Seoul National University Bundang Hospital also found that the mortality rate from influenza was highest among those aged 80 and older. 🇰🇷 Korea According to the Department of Respiratory Medicine at Seoul St. Mary's Hospital, the mortality rate for severe pneumonia in elderly patients treated in the ICU ranges from 35 to 50%.
🇺🇸 U.S. The U.S. Centers for Disease Control and Prevention (CDC) estimates that adults aged 65 and older account for up to 70% of flu-related hospitalizations and up to 85% of flu-related deaths. The 2024–2025 season was the first year the CDC classified as a 'high-risk season for all ages' since 2017–2018. Pneumonia is also counted among the leading causes of death in older adults. Due to immunosenescence, older adults face a markedly higher risk than younger people of progressing not only to severe infection but also to complications such as sepsis and multiple organ failure.
So what can be done? The first thing experts emphasize is vaccination. 🇰🇷 Korea Since 2013, the Korea Disease Control and Prevention Agency (질병관리청) has operated a national program that fully covers the cost of the 23-valent pneumococcal polysaccharide vaccine (PPSV23) for adults aged 65 and older. It can be received free of charge at designated medical institutions or public health centers nationwide and is provided once per lifetime. Influenza vaccination is also offered free of charge each autumn to adults aged 65 and older. 🇰🇷 Korea The 질병관리청 recommends that older adults with underlying conditions first consult their physician about options such as whether to choose a protein conjugate vaccine.
🇺🇸 U.S. According to the 2024 National Health Interview Survey conducted by the U.S. National Center for Health Statistics (NCHS), the influenza vaccination rate among U.S. adults aged 65 and older was 67.1% and the pneumococcal vaccination rate was 64.7%, both lower than in 2019 (70.5% and 67.0%, respectively). 🇺🇸 U.S. Medicare enrollees can receive flu, pneumococcal, and shingles (Shingrix) vaccines at no out-of-pocket cost. Korean-American families living in the United States are strongly encouraged to verify whether vaccination benefits are covered under their parents' Medicare plan.
Beyond vaccination, there are everyday habits families can practice together. Regular light exercise helps activate immune cells, and a balanced diet with adequate protein forms the foundation of immune function. Managing chronic conditions well is also important, as older adults with diabetes or heart disease face an even higher risk of flu and pneumonia complications. And the family's own attitude matters: not dismissing symptoms with 'it's probably just a cold' — that willingness to act rather than wait and see can genuinely make the difference between life and death.
Sources: Statistics Korea 2024 Cause-of-Death Statistics (Policy Briefing, 2025), Statistics Korea 2024 Elderly Statistics (National Data Center), 질병관리청 (Korea Disease Control and Prevention Agency) National Pneumococcal Vaccination Program for Older Adults (Government24), Department of Respiratory Medicine at Seoul Asan Hospital (Seoul St. Mary's Hospital) materials, Big-data influenza research by Professor Lee Hye-jin's team at Seoul National University Bundang Hospital (Medical World News), CDC/NCHS Data Brief No. 547 Vaccinations Among Adults Age 65 and Older: United States 2024 (2026.01), CDC MMWR 2024–25 Influenza Season Report, AARP Health (2026.02), Frontiers in Aging — Immunosenescence (2024), MDPI Vaccines — Immunosenescence Review (2024).
Note: This article was compiled by AI from the sources cited above. We strive for accuracy, but for decisions about your specific situation, please confirm the latest guidance from a professional or the relevant agency.