Pneumonia

(noo-MOH-nyuh) A severe inflammation of the lungs in which the alveoli (tiny air sacs) are filled with fluid. This may cause a decrease in the amount of oxygen that blood can absorb from air breathed into the lung. Pneumonia is usually caused by infection but may also be caused by radiation therapy, allergy, or irritation of lung tissue by inhaled substances. It may involve part or all of the lungs.

Pneumonia is an infection of the lungs that can cause mild to severe illness in people of all ages. Signs of pneumonia can include coughing, fever, fatigue, nausea, vomiting, rapid breathing or shortness of breath, chills, or chest pain. Certain people are more likely to become ill with pneumonia. This includes adults 65 years of age or older and children younger than 5 years of age. People younger than 64 years of age who have underlying medical conditions (like diabetes or HIV/AIDS) and people 19 through 64 who smoke cigarettes or have asthma are also at increased risk for getting pneumonia.