Introduction
Pneumonia is an infection that inflames the air sacs (alveoli) in one or both lungs. The air sacs may fill with fluid or pus, causing symptoms such as cough, fever, chills, and difficulty breathing. Pneumonia can range from mild to life-threatening and is a significant cause of illness in children, older adults, and people with weakened immune systems. Early recognition and treatment are important for a full recovery.
Causes
Pneumonia can be caused by a variety of organisms, including bacteria, viruses, and, less commonly, fungi. The most common bacterial cause is Streptococcus pneumoniae. Other bacteria, such as Haemophilus influenzae and Mycoplasma pneumoniae, can also cause pneumonia. Viral pneumonia is often caused by influenza, respiratory syncytial virus (RSV), and, more recently, SARS-CoV-2 (the virus responsible for COVID-19). Fungal pneumonia is rare and usually affects people with weakened immune systems. The infection can be acquired in the community (community-acquired pneumonia) or in healthcare settings (hospital-acquired pneumonia).
Symptoms
Symptoms of pneumonia can vary depending on the cause, age, and overall health of the individual. Common symptoms include:
- Cough, which may produce green, yellow, or bloody mucus
- Fever and chills
- Shortness of breath
- Chest pain, especially when breathing or coughing
- Fatigue and weakness
- Loss of appetite
- Confusion, especially in older adults
- Rapid or shallow breathing
In infants and young children, symptoms may also include vomiting, difficulty feeding, irritability, and bluish lips or fingertips.
Diagnosis
Diagnosis of pneumonia is based on a combination of medical history, physical examination, and diagnostic tests. A healthcare provider will listen to the lungs for abnormal sounds, such as crackles or wheezing. Chest X-rays are commonly used to confirm the diagnosis and assess the extent of lung involvement. Blood tests, sputum cultures, and pulse oximetry (to measure oxygen levels) may also be performed to identify the cause and severity of the infection.
Treatment Options
Treatment for pneumonia depends on the underlying cause and the severity of the illness. Bacterial pneumonia is typically treated with antibiotics. Viral pneumonia may be managed with antiviral medications in some cases, but most often, supportive care such as rest, fluids, and fever reducers is recommended. Hospitalization may be necessary for severe cases, especially in young children, older adults, or those with underlying health conditions. Supportive treatments in the hospital may include oxygen therapy, intravenous fluids, and respiratory support.
Prevention
Preventing pneumonia involves several strategies. Vaccination is one of the most effective ways to reduce the risk, with vaccines available for influenza, pneumococcus, and certain other pathogens. Practicing good hand hygiene, avoiding smoking, and managing chronic health conditions can also help prevent pneumonia. For vulnerable individuals, avoiding close contact with people who have respiratory infections is important.
When to Seek Medical Care
Seek medical attention promptly if you or someone you care for experiences:
- Difficulty breathing or shortness of breath
- Chest pain or persistent high fever
- Coughing up blood or large amounts of mucus
- Confusion or sudden changes in mental state
- Bluish lips or fingertips
- Severe weakness or inability to eat or drink
Takeaway
Pneumonia is a potentially serious lung infection that can affect anyone, but certain groups are at higher risk for complications. Early diagnosis, appropriate treatment, and preventive measures such as vaccination are key to reducing the impact of pneumonia and promoting a full recovery.