Pneumonia is an infection that inflames the air sacs in one or both lungs, leading to difficulty in breathing and a range of other symptoms. These air sacs, known as alveoli, may fill with fluid or pus, making it hard for oxygen to reach the bloodstream. Pneumonia can be caused by various pathogens, including bacteria, viruses, and fungi. The severity of the disease can vary significantly, with some cases being mild and others requiring hospitalization, particularly in vulnerable populations like infants, the elderly, and individuals with pre-existing health conditions.
Symptoms of pneumonia often include a persistent cough, chest pain, fever, and difficulty breathing. While the onset can be sudden, especially in cases caused by bacteria, viral pneumonia may develop more gradually. Diagnosis typically involves a physical examination, chest X-rays, and lab tests to determine the causative agent. Treatment depends on the type of pneumonia; bacterial pneumonia is usually treated with antibiotics, while viral pneumonia may require antiviral medications or supportive care, such as hydration and rest. Vaccinations are also available to help prevent certain types of pneumonia, further underscoring the importance of staying informed about this common yet serious infection.