What is pneumonia?
Pneumonia is a lung infection that can range from mild to so severe that you need to go to a hospital.
This happens when an infection causes the air sacs in your lungs (your doctor will call them alveoli) to fill with fluid or pus. This can prevent you from inhaling enough oxygen to reach your bloodstream.
Anyone can get this infection in the lungs. But infants under 2 and people over 65 are at greater risk. This is because their immune system may not be strong enough to fight it off.
You can get pneumonia in one or both lungs. You can also have it and not know it. Doctors call it walking pneumonia. The causes include bacteria, viruses, and fungi. If your pneumonia is caused by bacteria or a virus, you can pass it on to someone else.
Lifestyle habits, such as smoking cigarettes and drinking too much alcohol, can also increase your risk of getting pneumonia.
Symptoms of pneumonia
Your symptoms may vary depending on the cause of your pneumonia, your age, and your general health. They usually develop over several days.
Common symptoms of pneumonia include:
- Chest pain when you breathe or cough
- Cough that produces phlegm or mucus
- Fatigue and loss of appetite
- Fever, sweating and chills
- Nausea, vomiting and diarrhea
- Shortness of breath
Along with these symptoms, the elderly and people with weakened immune systems may be confused or have changes in their mental awareness, or they may have a lower than normal body temperature.
Newborns and infants may not show any signs of infection. Or they may vomit, have a fever and cough, and appear restless or tired.
If you have a new cough, fever, or shortness of breath, call your doctor to find out if it could be COVID-19. Illness with the new coronavirus can also lead to pneumonia.
Causes of pneumonia
Bacteria, viruses or fungi can cause pneumonia.
Common causes include:
- Influenza virus
- Cold virus
- RSV virus (the main cause of pneumonia in babies 1 year or younger)
- The bacteria called Streptococcus pneumoniae and Mycoplasma pneumoniae
Some people in hospital get “ventilator-associated pneumonia” if they get the infection while using a ventilator, a machine that helps you breathe.
If you get pneumonia while you are in the hospital and you are not on a ventilator, it is called “hospital” pneumonia. But most people get “community-acquired pneumonia,” which means they didn’t get it in the hospital.
Diagnosis of pneumonia
Your doctor will start by asking you about your symptoms and medical history, such as whether you smoke and have been around sick people at home, at school, or at work. Then they will listen to your lungs. If you have pneumonia, they may hear crackles, bubbles, or growls when you inhale.
If your doctor thinks you might have pneumonia, they will likely give you tests, including:
- Blood tests to look for signs of bacterial infection
- A chest x-ray to find the infection in your lungs and how far it has spread
- Pulse oximetry to measure the level of oxygen in your blood
- A sputum test to check the fluid in your lungs for the cause of an infection
If your symptoms started in the hospital or if you have other health problems, your doctor may order other tests, such as:
- An arterial blood gas test to measure oxygen in a small amount of blood drawn from one of your arteries
- Bronchoscopy to check your airways for blockages or other problems
- A CT scan to get a more detailed picture of your lungs
- A culture of pleural fluid, in which the doctor takes a small amount of fluid from the tissues around your lungs to look for bacteria that could cause pneumonia
Complications of pneumonia
Pneumonia can have complications, including:
- Bacteremia, in which bacteria spread to your blood. This can cause septic shock and organ failure.
- Difficulty breathing, which may mean you need to use a breathing machine while your lungs are healing.
- Fluid build-up between the layers of tissue that line your lungs and chest cavity. This fluid can also become infected.
- Lung abscess, when a pocket of pus forms in or around your lungs.
Treatment of pneumonia
Your doctor can tell you which treatment is right for you.
If you have bacterial pneumonia, you will be given antibiotics. Make sure you take all the medicines your doctor gives you, even if you start to feel better before you are finished.
If you have viral pneumonia, antibiotics won’t help. You will need to rest, drink plenty of fluids, and take fever medicine.
If your symptoms are severe, or if you have other conditions that make you more likely to have complications, your doctor may send you to the hospital. While you are at it, your doctor will likely give you fluids or antibiotics through an IV tube. You might even need oxygen therapy or respiratory treatments.
With any type of pneumonia, recovery will take time. You are going to need a lot of rest. You might need a week off from your usual routines, and you might still feel tired for a month.