Pneumonia:
It is an infection in one or both of your lungs caused by bacteria, viruses or fungi. When there is an infection in the lungs, several things happen, including:
- Your airways swell (become inflamed)
- The air sacs in the lungs fill with mucus and other fluids
It is an infection that inflames the air sacs in one or both lungs. The air sacs may fill with fluid or pus (purulent material), causing cough with phlegm or pus, fever, chills, and difficulty breathing. A variety of organisms, including bacteria, viruses and fungi, can cause pneumonia.
It can range in seriousness from mild to life-threatening. It is most serious for infants and young children, people older than age 65, and people with health problems or weakened immune systems.
Signs and symptoms of pneumonia may include:
- Chest pain when you breathe or cough
- Confusion or changes in mental awareness (in adults age 65 and older)
- Cough, which may produce phlegm
- Fatigue
- Fever, sweating and shaking chills
- Lower than normal body temperature (in adults older than age 65 and people with weak immune systems)
- Nausea, vomiting or diarrhea
- Loss of appetite
- Sweating
- Chills
- Shortness of breath
Newborns and infants may not show any sign of the infection. Or they may vomit, have a fever and cough, appear restless or tired and without energy, or have difficulty breathing and eating.
Causes:
The most common are bacteria and viruses in the air we breathe. Your body usually prevents these germs from infecting your lungs. But sometimes these germs can overpower your immune system, even if your health is generally good.
It is classified according to the types of germs that cause it and where you got the infection.
Community-acquired:
Community-acquired is the most common type. It occurs outside of hospitals or other health care facilities. It may be caused by:
- Bacteria: The most common cause in the U.S. is Streptococcus pneumoniae. This type can occur on its own or after you’ve had a cold or the flu. It may affect one part (lobe) of the lung, a condition called lobar pneumonia.
- Bacteria-like organisms: Mycoplasma pneumoniae also can cause pneumonia. It typically produces milder symptoms than do other types of pneumonia. Walking pneumonia is an informal name given to this type which typically isn’t severe enough to require bed rest.
- Fungi: This type is most common in people with chronic health problems or weakened immune systems, and in people who have inhaled large doses of the organisms. The fungi that cause it can be found in soil or bird droppings and vary depending upon geographic location.
- Viruses, including COVID-19: Some of the viruses that cause colds and the flu can cause pneumonia. Viruses are the most common cause in children younger than 5 years. Viral pneumonia is usually mild. But in some cases it can become very serious. Coronavirus 2019 (COVID-19) may cause pneumonia, which can become severe.
Hospital-acquired :
Some people catch pneumonia during a hospital stay for another illness. Hospital-acquired pneumonia can be serious because the bacteria causing it may be more resistant to antibiotics and because the people who get it are already sick. People who are on breathing machines (ventilators), often used in intensive care units, are at higher risk of this type of pneumonia.
Health care-acquired:
Health care-acquired pneumonia is a bacterial infection that occurs in people who live in long-term care facilities or who receive care in outpatient clinics, including kidney dialysis centers. Like hospital-acquired pneumonia, health care-acquired pneumonia can be caused by bacteria that are more resistant to antibiotics.
Aspiration pneumonia:
Aspiration pneumonia occurs when you inhale food, drink, vomit or saliva into your lungs. Aspiration is more likely if something disturbs your normal gag reflex, such as a brain injury or swallowing problem, or excessive use of alcohol or drugs.
Prevention:
- Get vaccinated
- Make sure children get vaccinated
- Practice good hygiene
- Don’t smoke
- Keep your immune system strong.