Pneumonia is an infection within one or both lungs. It can be caused by a number of germs, including bacteria, viruses, or, in rare cases, fungi or parasites.
Pneumonia is a common infection. It is more common in men than women and in smokers compared to non-smokers. It is also potentially serious and even life-threatening.
Healthcare providers separate pneumonia into different types based on where the infection occurred or on the germ that caused it.
Some different types include:
- Community-acquired pneumonia
- Hospital-acquired pneumonia
- Healthcare-associated pneumonia.
Each of the different types of pneumonia can be caused by a number of possible viruses, bacteria, fungi, or parasites. Viruses are thought to cause more infections than bacteria.
Viral pneumonia is more common in children than in adults. Up to 30 percent of cases in adults are caused by viruses. Up to 35 percent of all cases of pneumonia in children are thought to be from viruses
(see Pneumonia in Children).
Overall, the most common cause of pneumonia is the bacterium Streptococcus pneumoniae, also known as just pneumococcus.
In people with normal, functioning immune systems, fungal pneumonia is rather uncommon.
(Click Causes of Pneumonia for more information on the specific bacteria and viruses that most often cause pneumonia.)
Walking Pneumonia Versus Regular Pneumonia
Walking pneumonia is simply a milder case of pneumonia. In this case, a person does not appear as sick as someone with regular pneumonia -- they are still able to "walk around." They may feel sick; however, their symptoms are not as severe.
Walking pneumonia can be caused by a number of different types of bacteria and viruses. The most common type is caused by the bacterium
Mycoplasma pneumoniae (see Mycoplasma Pneumonia).
Walking pneumonia is common, accounting for about 20 percent of pneumonia cases in middle and high school students and up to 50 percent of cases in college students and military recruits.
How Contagious Is Pneumonia?
The germs that cause pneumonia are contagious. When spread, they typically cause upper respiratory symptoms such as a cough, runny nose, or
sore throat.
The germs that cause pneumonia are usually found in the mouth and nose of the infected person. They can be spread easily to another person either through the air or by touching a contaminated surface. Most often, they enter the person's body through the mouth, nose, or eyes.
Pneumonia and Its Symptoms
Common symptoms of this condition can vary from mild to severe. They include:
- A cough that produces green or yellow phlegm
- Trouble breathing
- Chest pain when breathing or coughing
- A rapid heart rate and breathing rate
- Fever (temperature greater than 100.5ºF or 38ºC)
- Chills.
Symptoms may also include nausea, vomiting, or
diarrhea.
How Is Pneumonia Treated?
Before deciding on a person's treatment, a healthcare provider will consider:
- The cause of pneumonia
- How severe the symptoms are
- The person's age
- The person's overall health.
People who have more severe symptoms or underlying health problems may need treatment in the hospital. However, most people can be treated at home. The goals of treatment are to cure the infection and prevent complications.
Antibiotics may be prescribed
(see Antibiotics and Pneumonia). They should be taken exactly as prescribed. This will decrease the chances of the antibiotic not completely eliminating the infection.
Getting plenty of rest and drinking fluids will also help.
Acetaminophen (
Tylenol®) or
ibuprofen (Advil
®,
Motrin®) can be used for pain relief and/or fever. Cough medicines are usually not recommended. The only time they are recommended is to help a person sleep.
Are You at Risk for Serious Pneumonia?
Pneumonia and its symptoms can vary from mild to severe. Many factors affect how serious the condition is, such as the type of germ causing the infection and the person's age and overall health.
Pneumonia tends to be more serious for:
- Infants and young children.
- Older adults (people age 65 or older).
- People who have weak immune systems as a result of diseases or other factors. These may include HIV/AIDS, chemotherapy, or an organ or bone marrow transplant.
It usually takes three to five days before a person with pneumonia starts to feel better. It can take three weeks or more before a person feels well enough to go back to his or her normal routines. Fatigue and a mild cough can last for a month or more.
The exact amount of time that pneumonia lasts, however, varies. Many of the same conditions that increase a person's risk for pneumonia
(see Pneumonia Risk Factors) also increase the time that it takes for the person to feel better. Age, the severity of initial symptoms, and the germ causing the illness also play a role in how long it takes before people start to feel better, along with when they feel back to normal.
Vaccines to Prevent Bacterial Pneumonia
Several vaccines are available to prevent certain
types of pneumonia. These vaccines can't prevent all cases, but they definitely help. Some of these products include:
