What Is It?
Pneumonia starts when a virus, fungus, or bacterium get into one of your lungs. (If it’s in both lungs, it’s called double pneumonia.) It causes the tiny sacs inside to get inflamed and fill with fluid or pus. If you’re healthy and get treated right away, it usually isn’t serious. But it can be dangerous for young kids, the elderly, and people who have other health problems or weak immune systems.
How It Happens
Most of the time, your body filters germs from the air to protect your lungs. Coughing also helps keep them out. If they do get in, your immune system usually fights them off before they make you sick. But if the germ is really strong or your body can’t do its part, your lungs can get infected. When your immune system sends cells to attack the germs, your lungs get inflamed, and that leads to pneumonia.
You may have a high fever, chills, shortness of breath, and chest pain when you breathe. You’ll also probably have a deep cough that doesn’t go away and brings up a thick liquid called phlegm. If you’re able to go about your daily business with these symptoms, you might have “walking pneumonia,” which is often caused by a certain kind of bacteria called Mycoplasma pneumoniae. But if your symptoms are worse than that, you should see your doctor.