Pneumonia Types Community Acquired

Community-acquired pneumonia refers to any case of pneumonia contracted outside of a hospital or extended care facility. As such, a case of community-acquired pneumonia may in fact be one of many types of pneumonia.

Types of Pneumonia in the Community

Most types of community-acquired pneumonia are viral or bacterial in nature. The bacterium Streptococcus pneumoniae causes from 20 to 60 percent of all community-acquired pneumonia cases. Other organisms responsible for community pneumonia include:

  • Chlamydia pneumoniae
  • Haemophilus influenza
  • Influenza A
  • Legionella (responsible for Legionnaires’ disease, a type of pneumonia caused by waterborne bacteria)
  • Mycoplasma pneumoniae.

In up to 30 to 50 percent of cases, the cause of community-acquired pneumonia is not known.

Community-Acquired Pneumonia Risk Factors

Community-acquired pneumonia includes both typical and atypical types of pneumonia. Typical pneumonia usually affects the elderly and the very young, while atypical pneumonia often occurs in young adults.

Those over the age of 65 are at particular risk for contracting community-acquired pneumonia. Along with age, a number of medical conditions increase the risk of community-acquired pneumonia, including:

  • AIDS
  • Asthma
  • Cerebrovascular disease
  • Congestive heart failure
  • COPD (chronic obstructive pulmonary disease)
  • Diabetes
  • Liver failure.

Diseases that compromise the immune system, as well as use of corticosteroids and immune-suppressing medications, also put an individual at heightened risk for contracting community-acquired pneumonia.

Community-Acquired Pneumonia Symptoms

Community-acquired pneumonia symptoms vary depending on the infectious agent that causes the pneumonia. However, some common community-acquired pneumonia symptoms are:

  • Chest pain
  • Chills
  • Cough
  • Dyspnea (shortness of breath)
  • Fatigue
  • Fever
  • Shivering.

In such cases of pneumonia, symptoms vary depending on the patient’s age. Pneumonia coughs, for instance, tend to bring up mucus in older children and young adults, but are dry in the elderly and very young. The elderly may seem confused with impaired mental abilities during pneumonia, while children may become restless and irritable.

Community-Acquired Pneumonia Complications

In some cases, community-acquired pneumonia can be fatal. In fact, according to the Centers for Disease Control and Prevention, influenza and pneumonia are the seventh leading causes of death in the United States.

The risk of death increases if the community-acquired pneumonia is caused by aspiration (the inhaling of foreign particles into the lungs), if the patient is elderly, or if the patient suffers from other conditions (particularly those that weaken the immune system).

Pneumonia may also cause systemic sepsis, a body-wide immune response that causes widespread inflammation and potentially severe complications.

Community-Acquired Pneumonia Treatment

Treatment for this type of pneumonia depends on the infectious agent causing the disease. In cases of viral pneumonia, treatment is usually bed rest and fluid intake, while bacterial causes of community-acquired pneumonia are treated with antibiotics. Unfortunately, several strains of pneumonia-causing bacteria, including Streptococcus pneumoniae, have demonstrated resistance to commonly-used antibiotics. Severe cases of community-acquired pneumonia may require hospitalization with intravenous antibiotics or antiviral medication.


Chang, L., et al. (2006). Diagnosis and treatment of community-acquired pneumonia. Retrieved March 8, 2010, from the American Academy of Family Physicians Web site:

Merck Manuals Online Medical Library Staff. (2008). Community-acquired pneumonia. Retrieved March 8, 2010, from the Merck Web site:

Schmitt, S. (n.d.). Community-acquired pneumonia. Retrieved March 8, 2010, from the Cleveland Clinic Web site: