Pneumonia is an infection that causes inflammation in the air sacs (alveoli) of one or both lungs, leading them to fill with fluid or pus. This makes it harder for oxygen to reach the bloodstream, resulting in symptoms such as cough (often with phlegm), fever, chills, shortness of breath, and chest pain. It can be caused by bacteria, viruses, or fungi, and its severity ranges from mild to life-threatening, especially in infants, the elderly, and those with weakened immune systems. 🎥 DR. SINGH |