Pneumonia
Whether or not this lung infection is contagious depends on what caused it. Two types of pneumonia that can’t be spread from person to person are fungal pneumonia, which is contracted from the environment, and aspiration pneumonia, which occurs when food or liquid is inhaled into the lungs. On the other hand, bacterial and viral pneumonia—which cause most cases of pneumonia, according to the American Lung Association—are indeed contagious, though not in the way you might think. “The causative microorganism may move between people but may not automatically cause pneumonia,” says Dr. Adalja. “For example, some bacteria may just colonize the nasal passages, while influenza, which can cause pneumonia, may cause bronchitis in another individual.”
Whether or not this lung infection is contagious depends on what caused it. Two types of pneumonia that can’t be spread from person to person are fungal pneumonia, which is contracted from the environment, and aspiration pneumonia, which occurs when food or liquid is inhaled into the lungs. On the other hand, bacterial and viral pneumonia—which cause most cases of pneumonia, according to the American Lung Association—are indeed contagious, though not in the way you might think. “The causative microorganism may move between people but may not automatically cause pneumonia,” says Dr. Adalja. “For example, some bacteria may just colonize the nasal passages, while influenza, which can cause pneumonia, may cause bronchitis in another individual.”