November 12 marks "World Pneumonia Day," established to raise awareness and reduce preventable deaths caused by pneumonia. Experts emphasize that because pneumonia is a major cause of mortality—particularly among older adults in South Korea—greater attention must be paid to vaccination and preventive measures.

According to national cause-of-death statistics from last year, pneumonia ranked as the third leading cause of death in South Korea, following cancer and heart disease. Among adults aged 80 and older, it was the second leading cause of death after cancer. Pneumonia is especially dangerous for older populations because aging weakens pulmonary immune functions, reducing the body's ability to block bacteria and viruses and clear them through coughing. Furthermore, older adults often exhibit atypical symptoms—such as loss of appetite, rapid fatigue, and altered consciousness—rather than classic respiratory signs like fever and cough, making early detection difficult.

Even in healthy adults, early symptoms of pneumonia resemble a common cold—including coughing, phlegm, and fever—making it easy to miss the window for timely treatment. If breathing becomes difficult, chest pain is felt, or symptoms do not improve over time, individuals should seek medical evaluation rather than dismissing it as a simple cold. Those with underlying conditions such as diabetes, cardiovascular disease, or chronic obstructive pulmonary disease (COPD) face a high risk of pneumonia deteriorating into sepsis or respiratory failure. Additionally, prolonged hospitalization can diminish physical function, leaving patients struggling with mobility even after a full recovery.

While pneumonia is caused by infections from bacteria, viruses, and other pathogens, its progression is heavily influenced by individual immune function. Professor Lee Jong-min from the Division of Pulmonary Medicine at Seoul St. Mary's Hospital, Catholic University of Korea, explained, "Various bacteria and viruses normally reside in the oral cavity and pharynx. Micro-aspirations—where small amounts of saliva and secretions containing bacteria are inhaled into the airways—occur repeatedly. In healthy individuals, the pulmonary immune system and airway defense mechanisms eliminate these bacteria, preventing most cases from developing into pneumonia. However, when immunity declines or airway defense functions are weakened by viral infections like a cold, bacteria easily proliferate in the lungs, ultimately leading to pneumonia."

Secondary bacterial infections following viral illnesses—such as influenza or respiratory syncytial virus (RSV)—are also common. Viruses damage epithelial cells on the airway surface and impair the function of cilia, which normally expel mucus and foreign matter, creating an environment where bacteria can easily invade and multiply. When bacteria infiltrate a respiratory defense system weakened in this way and trigger secondary pneumonia, older adults, individuals with chronic illnesses, and immunocompromised patients face a high risk of progression to severe pneumonia.

Because treatment methods vary depending on the cause of pneumonia, accurate diagnosis is crucial. Bacterial pneumonia requires antibiotic therapy, whereas viral pneumonia is treated with antiviral medications or supportive care, depending on the viral type and the patient's condition. Severe cases may require inpatient treatment alongside respiratory support therapies such as oxygen supplementation.

To prevent contracting or worsening pneumonia, appropriate vaccinations are essential. In particular, older adults should receive the annual influenza vaccine and consult healthcare professionals about getting vaccinated against pneumococcal disease, COVID-19, and RSV depending on their health status. Everyday preventive practices for pneumonia include washing hands after returning home, wearing masks when visiting crowded indoor spaces, and maintaining good oral hygiene through regular brushing. Keeping fit through regular physical activity and sufficient sleep maintains overall health, while smokers are strongly advised to quit.

Professor Lee advised, "Older adults are prone to nutritional imbalances due to decreased appetite or declining digestive function. Inadequate nutritional intake leads to weakened immune function, making them vulnerable to various infections. Therefore, rather than relying on specific foods, it is advisable to maintain regular and well-balanced meals."

[ⓒ Global Economic Times. 무단전재-재배포 금지]