Table of ContentsView AllTable of ContentsCommon CausesHealth Risk FactorsLifestyle Risk FactorsFrequently Asked QuestionsNext in Pneumonia GuideHow Pneumonia Is Diagnosed
Table of ContentsView All
View All
Table of Contents
Common Causes
Health Risk Factors
Lifestyle Risk Factors
Frequently Asked Questions
Next in Pneumonia Guide
© Verywell, 2018
Pneumonia isn’t one single disease, and the cause determines whattreatmentis needed.
Bacteria
Bacterial pneumonia is the most common type of pneumonia and often only affects one area of your lung.It sometimes occurs after you’ve had some other type of infection that weakens your immune system, like a cold or the flu, but the condition can also occur on its own without a preceding infection.
Bacterial pneumonia is usually treated with antibiotics.
Examples of bacteria that can cause bacterial pneumonia include:
Atypical Bacteria
Atypical bacteria are bacteria that are unable to be cultured with standard methods. Atypical bacteria that cause pneumonia include:
Viruses
Most people with viral pneumonia recover within one to three weeks without treatment, though some cases become severe and require hospitalization.
Examples of viruses that can cause viral pneumonia include:
Fungi
Fungal pneumonia is caused when spores enter your lungs and multiply. It commonly occurs in people with compromised immune systems or chronic health problems.However, it can occur in otherwise healthy adults too.
Fungal infections that are picked up from the soil in certain areas of the United States can lead to fungal pneumonia, including:
Understanding White Lung Pneumonia: A Diagnostic Finding
Aspiration
Aspiration happens when a foreign object, such as a piece of food, gum, liquid, or vomit, is inhaled. The object then becomes lodged in one or both lungs where it’s trapped, unless you’re able to cough it up. When you aspirate a foreign object or liquid, it increases the presence of bacteria as the object begins to rot, leading to an infection.
Aspiration pneumonia, or the collection of infectious material in the lungs due to the presence of a foreign object, can make it difficult to breathe.
Some people may have an ongoing condition where they accidentally swallow food into their lungs instead of into their esophagus, the tube that moves food to the stomach. Many people never even realize that a piece of food has gone down the “wrong pipe.” This problem is more common in the elderly, who are more likely to have problems with swallowing. The risk of pneumonia due to aspiration while underanesthesiais also why patients are asked not to eat or drink prior to surgery.
Pneumonia can affect anyone at any age, but the two age groups at the highest risk both for contracting it and for having more severe cases are children under age 2 and adults over age 65.
Other risk factors include:
Risk factors that may have to do with your lifestyle choices increase your likelihood of developing pneumonia and include:
It’s important to be aware that your risk of pneumonia increases with each additional health or lifestyle risk factor you have.
Yes. Children under 2 years of age are at risk because theirimmune systemsare still developing, and adults over age 65 have an increased risk because, as we age, our immune systems don’t fight off infections as well.
When the COVID-19 virus causes pneumonia, it typically involves both lungs. Usually, people recover from other types of pneumonia without lasting lung problems, but COVID-19-related pneumonia often leaves long-term scarring and stiffness that leads to lingeringinterstitial lung diseasein which it’s difficult to get enough air into your body.
How Pneumonia Is Diagnosed
21 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Cilloniz C, Martin-loeches I, Garcia-vidal C, San jose A, Torres A.Microbial Etiology of Pneumonia: Epidemiology, Diagnosis and Resistance Patterns. Int J Mol Sci. 2016;17(12) doi:10.3390/ijms17122120Abdul Sattar SB, Sharma S.Bacterial Pneumonia. Treasure Island, Fl: StatPearls Publishing.Henriques-normark B, Tuomanen EI.The pneumococcus: epidemiology, microbiology, and pathogenesis. Cold Spring Harb Perspect Med. 2013;3(7) doi:10.1101/cshperspect.a010215Chang TM, Mou CH, Shen TC, et al.Retrospective cohort evaluation on risk of pneumonia in patients with pulmonary tuberculosis. Medicine (Baltimore). 2016;95(26):e4000. doi:10.1097/MD.0000000000004000Bajantri B, Venkatram S, Diaz-fuentes G.A Potentially Severe Infection. J Clin Med Res. 2018;10(7):535-544. doi:10.14740/jocmr3421wPuljiz I, Kuzman I, Dakovic-rode O, Schönwald N, Mise B.Chlamydia pneumoniae and Mycoplasma pneumoniae pneumonia: comparison of clinical, epidemiological characteristics and laboratory profiles. Epidemiol Infect. 2006;134(3):548-55. doi:10.1017/S0950268805005522Leoni E, Catalani F, Marini S, Dallolio L.Legionellosis Associated with Recreational Waters: A Systematic Review of Cases and Outbreaks in Swimming Pools, Spa Pools, and Similar Environments. Int J Environ Res Public Health. 2018;15(8) doi:10.3390/ijerph15081612Ebeledike C, Ahmad T.Pediatric Pneumonia. Treasure Island, Fl: StatPearls Publishing.RSV | Home | Respiratory Syncytial Virus | CDC. Centers for Disease Control and Prevention.American Lung Association.What Causes Pneumonia?Centers for Disease Control and Prevention.Pneumocystis pneumonia | Fungal Diseases.Mckinsey DS, Mckinsey JP.Pulmonary histoplasmosis. Semin Respir Crit Care Med. 2011;32(6):735-44. doi:10.1055/s-0031-1295721Othman AA, Abdelazim MS.Ventilator-associated pneumonia in adult intensive care unit prevalence and complications. The Egyptian Journal of Critical Care Medicine. 2017;5(2):61-63. doi:10.1016/j.ejccm.2017.06.001Pneumonia. National Heart Lung and Blood Institute.Manabe T, Teramoto S, Tamiya N, Okochi J, Hizawa N.Risk Factors for Aspiration Pneumonia in Older Adults. PLoS ONE. 2015;10(10):e0140060. doi:10.1371/journal.pone.0140060Bello S, Menéndez R, Antoni T, et al.Tobacco smoking increases the risk for death from pneumococcal pneumonia. Chest. 2014;146(4):1029-1037. doi:10.1378/chest.13-2853Children: reducing mortality. World Health Organization.Loeb M, Neupane B, Walter SD, et al.Environmental risk factors for community-acquired pneumonia hospitalization in older adults. J Am Geriatr Soc. 2009;57(6):1036-40. doi:10.1111/j.1532-5415.2009.02259.xAmerican Lung Association.Learn about pneumonia.Cleveland Clinic.Pneumonia.Myall KJ, Mukherjee B, Castanheira AM, et al.Persistent post–covid-19 interstitial lung disease. An observational study of corticosteroid treatment.Annals ATS. 2021;18(5):799-806. doi:10.1513/annalsats.202008-1002ocAdditional ReadingAmerican Lung Association.Pneumonia.Marrie TJ.Epidemiology, Pathogenesis, and Microbiology of Community-Acquired Pneumonia in Adults. UpToDate.Mayo Clinic Staff.Pneumonia. Mayo Clinic.National Heart, Lung, and Blood Institute.Pneumonia. National Institutes of Health. U.S. Department of Health & Human Services.
21 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Cilloniz C, Martin-loeches I, Garcia-vidal C, San jose A, Torres A.Microbial Etiology of Pneumonia: Epidemiology, Diagnosis and Resistance Patterns. Int J Mol Sci. 2016;17(12) doi:10.3390/ijms17122120Abdul Sattar SB, Sharma S.Bacterial Pneumonia. Treasure Island, Fl: StatPearls Publishing.Henriques-normark B, Tuomanen EI.The pneumococcus: epidemiology, microbiology, and pathogenesis. Cold Spring Harb Perspect Med. 2013;3(7) doi:10.1101/cshperspect.a010215Chang TM, Mou CH, Shen TC, et al.Retrospective cohort evaluation on risk of pneumonia in patients with pulmonary tuberculosis. Medicine (Baltimore). 2016;95(26):e4000. doi:10.1097/MD.0000000000004000Bajantri B, Venkatram S, Diaz-fuentes G.A Potentially Severe Infection. J Clin Med Res. 2018;10(7):535-544. doi:10.14740/jocmr3421wPuljiz I, Kuzman I, Dakovic-rode O, Schönwald N, Mise B.Chlamydia pneumoniae and Mycoplasma pneumoniae pneumonia: comparison of clinical, epidemiological characteristics and laboratory profiles. Epidemiol Infect. 2006;134(3):548-55. doi:10.1017/S0950268805005522Leoni E, Catalani F, Marini S, Dallolio L.Legionellosis Associated with Recreational Waters: A Systematic Review of Cases and Outbreaks in Swimming Pools, Spa Pools, and Similar Environments. Int J Environ Res Public Health. 2018;15(8) doi:10.3390/ijerph15081612Ebeledike C, Ahmad T.Pediatric Pneumonia. Treasure Island, Fl: StatPearls Publishing.RSV | Home | Respiratory Syncytial Virus | CDC. Centers for Disease Control and Prevention.American Lung Association.What Causes Pneumonia?Centers for Disease Control and Prevention.Pneumocystis pneumonia | Fungal Diseases.Mckinsey DS, Mckinsey JP.Pulmonary histoplasmosis. Semin Respir Crit Care Med. 2011;32(6):735-44. doi:10.1055/s-0031-1295721Othman AA, Abdelazim MS.Ventilator-associated pneumonia in adult intensive care unit prevalence and complications. The Egyptian Journal of Critical Care Medicine. 2017;5(2):61-63. doi:10.1016/j.ejccm.2017.06.001Pneumonia. National Heart Lung and Blood Institute.Manabe T, Teramoto S, Tamiya N, Okochi J, Hizawa N.Risk Factors for Aspiration Pneumonia in Older Adults. PLoS ONE. 2015;10(10):e0140060. doi:10.1371/journal.pone.0140060Bello S, Menéndez R, Antoni T, et al.Tobacco smoking increases the risk for death from pneumococcal pneumonia. Chest. 2014;146(4):1029-1037. doi:10.1378/chest.13-2853Children: reducing mortality. World Health Organization.Loeb M, Neupane B, Walter SD, et al.Environmental risk factors for community-acquired pneumonia hospitalization in older adults. J Am Geriatr Soc. 2009;57(6):1036-40. doi:10.1111/j.1532-5415.2009.02259.xAmerican Lung Association.Learn about pneumonia.Cleveland Clinic.Pneumonia.Myall KJ, Mukherjee B, Castanheira AM, et al.Persistent post–covid-19 interstitial lung disease. An observational study of corticosteroid treatment.Annals ATS. 2021;18(5):799-806. doi:10.1513/annalsats.202008-1002ocAdditional ReadingAmerican Lung Association.Pneumonia.Marrie TJ.Epidemiology, Pathogenesis, and Microbiology of Community-Acquired Pneumonia in Adults. UpToDate.Mayo Clinic Staff.Pneumonia. Mayo Clinic.National Heart, Lung, and Blood Institute.Pneumonia. National Institutes of Health. U.S. Department of Health & Human Services.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Cilloniz C, Martin-loeches I, Garcia-vidal C, San jose A, Torres A.Microbial Etiology of Pneumonia: Epidemiology, Diagnosis and Resistance Patterns. Int J Mol Sci. 2016;17(12) doi:10.3390/ijms17122120Abdul Sattar SB, Sharma S.Bacterial Pneumonia. Treasure Island, Fl: StatPearls Publishing.Henriques-normark B, Tuomanen EI.The pneumococcus: epidemiology, microbiology, and pathogenesis. Cold Spring Harb Perspect Med. 2013;3(7) doi:10.1101/cshperspect.a010215Chang TM, Mou CH, Shen TC, et al.Retrospective cohort evaluation on risk of pneumonia in patients with pulmonary tuberculosis. Medicine (Baltimore). 2016;95(26):e4000. doi:10.1097/MD.0000000000004000Bajantri B, Venkatram S, Diaz-fuentes G.A Potentially Severe Infection. J Clin Med Res. 2018;10(7):535-544. doi:10.14740/jocmr3421wPuljiz I, Kuzman I, Dakovic-rode O, Schönwald N, Mise B.Chlamydia pneumoniae and Mycoplasma pneumoniae pneumonia: comparison of clinical, epidemiological characteristics and laboratory profiles. Epidemiol Infect. 2006;134(3):548-55. doi:10.1017/S0950268805005522Leoni E, Catalani F, Marini S, Dallolio L.Legionellosis Associated with Recreational Waters: A Systematic Review of Cases and Outbreaks in Swimming Pools, Spa Pools, and Similar Environments. Int J Environ Res Public Health. 2018;15(8) doi:10.3390/ijerph15081612Ebeledike C, Ahmad T.Pediatric Pneumonia. Treasure Island, Fl: StatPearls Publishing.RSV | Home | Respiratory Syncytial Virus | CDC. Centers for Disease Control and Prevention.American Lung Association.What Causes Pneumonia?Centers for Disease Control and Prevention.Pneumocystis pneumonia | Fungal Diseases.Mckinsey DS, Mckinsey JP.Pulmonary histoplasmosis. Semin Respir Crit Care Med. 2011;32(6):735-44. doi:10.1055/s-0031-1295721Othman AA, Abdelazim MS.Ventilator-associated pneumonia in adult intensive care unit prevalence and complications. The Egyptian Journal of Critical Care Medicine. 2017;5(2):61-63. doi:10.1016/j.ejccm.2017.06.001Pneumonia. National Heart Lung and Blood Institute.Manabe T, Teramoto S, Tamiya N, Okochi J, Hizawa N.Risk Factors for Aspiration Pneumonia in Older Adults. PLoS ONE. 2015;10(10):e0140060. doi:10.1371/journal.pone.0140060Bello S, Menéndez R, Antoni T, et al.Tobacco smoking increases the risk for death from pneumococcal pneumonia. Chest. 2014;146(4):1029-1037. doi:10.1378/chest.13-2853Children: reducing mortality. World Health Organization.Loeb M, Neupane B, Walter SD, et al.Environmental risk factors for community-acquired pneumonia hospitalization in older adults. J Am Geriatr Soc. 2009;57(6):1036-40. doi:10.1111/j.1532-5415.2009.02259.xAmerican Lung Association.Learn about pneumonia.Cleveland Clinic.Pneumonia.Myall KJ, Mukherjee B, Castanheira AM, et al.Persistent post–covid-19 interstitial lung disease. An observational study of corticosteroid treatment.Annals ATS. 2021;18(5):799-806. doi:10.1513/annalsats.202008-1002oc
Cilloniz C, Martin-loeches I, Garcia-vidal C, San jose A, Torres A.Microbial Etiology of Pneumonia: Epidemiology, Diagnosis and Resistance Patterns. Int J Mol Sci. 2016;17(12) doi:10.3390/ijms17122120
Abdul Sattar SB, Sharma S.Bacterial Pneumonia. Treasure Island, Fl: StatPearls Publishing.
Henriques-normark B, Tuomanen EI.The pneumococcus: epidemiology, microbiology, and pathogenesis. Cold Spring Harb Perspect Med. 2013;3(7) doi:10.1101/cshperspect.a010215
Chang TM, Mou CH, Shen TC, et al.Retrospective cohort evaluation on risk of pneumonia in patients with pulmonary tuberculosis. Medicine (Baltimore). 2016;95(26):e4000. doi:10.1097/MD.0000000000004000
Bajantri B, Venkatram S, Diaz-fuentes G.A Potentially Severe Infection. J Clin Med Res. 2018;10(7):535-544. doi:10.14740/jocmr3421w
Puljiz I, Kuzman I, Dakovic-rode O, Schönwald N, Mise B.Chlamydia pneumoniae and Mycoplasma pneumoniae pneumonia: comparison of clinical, epidemiological characteristics and laboratory profiles. Epidemiol Infect. 2006;134(3):548-55. doi:10.1017/S0950268805005522
Leoni E, Catalani F, Marini S, Dallolio L.Legionellosis Associated with Recreational Waters: A Systematic Review of Cases and Outbreaks in Swimming Pools, Spa Pools, and Similar Environments. Int J Environ Res Public Health. 2018;15(8) doi:10.3390/ijerph15081612
Ebeledike C, Ahmad T.Pediatric Pneumonia. Treasure Island, Fl: StatPearls Publishing.
RSV | Home | Respiratory Syncytial Virus | CDC. Centers for Disease Control and Prevention.
American Lung Association.What Causes Pneumonia?
Centers for Disease Control and Prevention.Pneumocystis pneumonia | Fungal Diseases.
Mckinsey DS, Mckinsey JP.Pulmonary histoplasmosis. Semin Respir Crit Care Med. 2011;32(6):735-44. doi:10.1055/s-0031-1295721
Othman AA, Abdelazim MS.Ventilator-associated pneumonia in adult intensive care unit prevalence and complications. The Egyptian Journal of Critical Care Medicine. 2017;5(2):61-63. doi:10.1016/j.ejccm.2017.06.001
Pneumonia. National Heart Lung and Blood Institute.
Manabe T, Teramoto S, Tamiya N, Okochi J, Hizawa N.Risk Factors for Aspiration Pneumonia in Older Adults. PLoS ONE. 2015;10(10):e0140060. doi:10.1371/journal.pone.0140060
Bello S, Menéndez R, Antoni T, et al.Tobacco smoking increases the risk for death from pneumococcal pneumonia. Chest. 2014;146(4):1029-1037. doi:10.1378/chest.13-2853
Children: reducing mortality. World Health Organization.
Loeb M, Neupane B, Walter SD, et al.Environmental risk factors for community-acquired pneumonia hospitalization in older adults. J Am Geriatr Soc. 2009;57(6):1036-40. doi:10.1111/j.1532-5415.2009.02259.x
American Lung Association.Learn about pneumonia.
Cleveland Clinic.Pneumonia.
Myall KJ, Mukherjee B, Castanheira AM, et al.Persistent post–covid-19 interstitial lung disease. An observational study of corticosteroid treatment.Annals ATS. 2021;18(5):799-806. doi:10.1513/annalsats.202008-1002oc
American Lung Association.Pneumonia.Marrie TJ.Epidemiology, Pathogenesis, and Microbiology of Community-Acquired Pneumonia in Adults. UpToDate.Mayo Clinic Staff.Pneumonia. Mayo Clinic.National Heart, Lung, and Blood Institute.Pneumonia. National Institutes of Health. U.S. Department of Health & Human Services.
American Lung Association.Pneumonia.
Marrie TJ.Epidemiology, Pathogenesis, and Microbiology of Community-Acquired Pneumonia in Adults. UpToDate.
Mayo Clinic Staff.Pneumonia. Mayo Clinic.
National Heart, Lung, and Blood Institute.Pneumonia. National Institutes of Health. U.S. Department of Health & Human Services.
Meet Our Medical Expert Board
Share Feedback
Was this page helpful?Thanks for your feedback!What is your feedback?OtherHelpfulReport an ErrorSubmit
Was this page helpful?
Thanks for your feedback!
What is your feedback?OtherHelpfulReport an ErrorSubmit
What is your feedback?
