Pneumonia is an acute infection of the lungs that inflames the air sacs (alveoli), which may fill with fluid or pus, causing cough, fever, chills, and difficulty breathing. It can be caused by bacteria, viruses, fungi, or inhaled irritants, and can range from mild to life-threatening, especially in young children, the elderly, or those with weakened immune systems. Early diagnosis and appropriate treatment are crucial to prevent complications such as sepsis, lung abscess, or respiratory failure.

• Persistent cough with phlegm or pus
• High fever, chills, and fatigue
• Shortness of breath or rapid breathing
• Chest pain, especially during coughing or deep breaths
• Treatment may include antibiotics, antiviral medications, oxygen therapy, and supportive care