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Cough
Fatigue
Fever
Malaise
Whooping cough
Phlegm
Chest pain
Shortness of breath
Chills
Loss of appetite
Green phlegm
Not seeing your symptoms? No worries!
Inflammation of the lungs. Symptoms include cough, increased phlegm, and fever. Some patients may experience breathlessness and chest pain. The most common cause is a bacterial infection.
Your doctor may ask these questions to check for this disease:
Treatment depends on the cause of pneumonia. Antibiotics will be given when bacteria is the cause. Depending on severity, some patients may also need hospitalization for oxygen therapy and monitoring.
Reviewed By:
Phillip Aguila, MD, MBA (Pulmonology, Critical Care)
Dr. Aguila graduated from West Virginia University School of Medicine. He has trained in Pulmonary and Critical Care Medicine at The University of North Carolina in Chapel Hill and Internal Medicine at Medical College of Pennsylvania/Hahnemann University at Allegheny General Hospital in Pittsburgh Pennsylvania. He has served as Assistant Professor since 2010.
Eisaku Kamakura, MD (Pulmonology)
Dr. Kamakura graduated from the Tokyo Medical and Dental University, School of Dentistry, and the Niigata University School of Medicine. He trained at Yokosuka Kyosai Hospital and held positions in the Respiratory Medicine departments at Yokosuka Kyosai Hospital, Tokyo Medical and Dental University, Ome City General Hospital, and Musashino Red Cross Hospital. In 2021, he became the specially appointed assistant professor at the Department of General Medicine, Niigata University School of Medicine.
Content updated on Feb 13, 2025
Following the Medical Content Editorial Policy
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Female, 20s
Ubie helped me understand my symptoms and eased my anxiety about the severity of my condition. Since it was suggested, I decided to see a doctor - better safe than sorry! Ubie provided me with the insight I needed regarding my doctor's visit. Usually, I only visit my primary care physician for routine checkups, but when Ubie indicated I potentially had pneumonia, I knew I needed to go. I'm glad I did, as the doctor's diagnosis matched Ubie's result.
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Q.
How Contagious Is Pneumonia? Risk by Close Contact and Household Spread
A.
Pneumonia can be contagious depending on the cause: viral and some bacterial or atypical infections can spread through close, repeated contact in households, while aspiration and other non infectious pneumonias do not. Risk of catching it rises with prolonged indoor exposure and in higher risk people like older adults, infants, smokers, and those with chronic conditions, and bacterial cases are usually less contagious after 24 to 48 hours of antibiotics; there are several factors to consider, including how long someone is contagious and practical steps to prevent spread, which are detailed below.
References:
* Prina E, Ranzani OT, Torres A. Community-acquired pneumonia. Lancet. 2015 Oct 31;386(10001):1097-108. doi: 10.1016/S0140-6736(15)60907-2. PMID: 26198197.
* Li J, Yu J, Liang X, Zhang T, Li J, Huang B, Zheng K, Qu C, Luo R, Tan M. Intrafamilial Transmission of Community-Acquired Pneumonia in Chinese Children: A Prospective Cohort Study. Pediatr Infect Dis J. 2018 Sep;37(9):e230-e235. doi: 10.1097/INF.0000000000002061. PMID: 29878297.
* Ladhani SN, Al-Mazrou A. Transmission of Streptococcus pneumoniae: a review of the epidemiology of nasopharyngeal carriage and the impact of vaccination. Int J Infect Dis. 2013 May;17(5):e370-82. doi: 10.1016/j.ijid.2012.10.019. Epub 2012 Oct 26. PMID: 23136544.
* Huang SS, Platt R, Rifas-Shiman SL, Kim M, Pelton SI, Bogaert D, Weycker D. Risk factors for household transmission of Streptococcus pneumoniae. Clin Infect Dis. 2012 Sep;55(6):839-47. doi: 10.1093/cid/cis566. Epub 2012 May 21. PMID: 22619472; PMCID: PMC3657519.
* Cilloniz C, Torres A, Niederman MS, van der Eerden M, Chalmers JD, Facciolongo N, Frommelt R, Blasi F. Community-acquired pneumonia: Epidemiology and risk factors. Semin Respir Crit Care Med. 2012 Oct;33(5):543-56. doi: 10.1055/s-0032-1325141. Epub 2012 Nov 21. PMID: 23412357.
Q.
Over 65: When It’s Safe to Resume Normal Activities After Antibiotics
A.
If you’re over 65 recovering from an infection, especially pneumonia, you’re usually much less contagious after 24 to 48 hours of antibiotics, but not contagious does not mean fully recovered; resume activities only after finishing the antibiotic course, being fever free for at least 48 hours, breathing comfortably at rest, and noticing steady improvement in cough, energy, and walking tolerance. There are several factors to consider. See below to understand more, including timelines, safe first steps, what to delay, key warning signs, and when to call a doctor.
References:
* Serafim V, Koutsiopoulou M, Tsiropoulos S, Gkouta A, Petropoulou N, Papadopoulou SK, Mitrou G, Kourtidou M, Chourdakis M, Goutzourelas N. Impact of Antibiotic Exposure on Gut Microbiota and Health in Older Adults: A Narrative Review. Nutrients. 2023 Sep 14;15(18):4030. doi: 10.3390/nu15184030. PMID: 37765103; PMCID: PMC10534212.
* Cunha BA, Cunha CB, Gallo C. Clostridioides difficile infection in older adults: treatment and prevention challenges. Ther Adv Infect Dis. 2021 May 10;9:20420556211016839. doi: 10.1177/20420556211016839. PMID: 34046200; PMCID: PMC8117765.
* Polk RE, Van Haren F, Pols M, Hekster YA, Nielen R, Van de Wetering N, Koudstaal M, Borgsteede SD. Adverse drug reactions to antibiotics in the elderly: a systematic review. BMC Geriatr. 2018 Jul 16;18(1):159. doi: 10.1186/s12877-018-0850-y. PMID: 30012170; PMCID: PMC6048792.
* Cohen S, Kuijpers M, van der Veen LB, van den Hout HMP, van der Werf TS, Netea MG, Kox M. Post-acute infection syndromes: a common problem in older adults? Curr Opin Infect Dis. 2023 Aug 1;36(4):258-266. doi: 10.1097/QCO.0000000000000912. Epub 2023 May 15. PMID: 37192305; PMCID: PMC10375631.
* Abdel-Fattah AM, Al-Attar K, Abdulghani M, Al-Attar A, Al-Attar M, Al-Khalifa R, Al-Khalifa A, Al-Khalifa H, Al-Khalifa M, Al-Khalifa F, Al-Attar H, Al-Attar F, Al-Attar S. Antibiotics in Older Adults: A Balancing Act Between Benefits and Risks. Drugs Aging. 2020 Feb;37(2):107-118. doi: 10.1007/s40266-019-00735-0. PMID: 31776735.
Q.
Parents: How to Protect the Rest of the Family When a Kid Has Pneumonia
A.
Protect your family when a child has pneumonia by targeting what actually spreads the virus or bacteria and using simple steps: frequent handwashing, no sharing cups or towels, daily cleaning of high touch surfaces, reasonable space, good airflow, and masks if close contact or high risk relatives are involved. There are several factors to consider, including who in the home is most vulnerable, how contagious the cause is, which vaccines help, what early symptoms to watch for, and when to seek medical care; see below for the complete guidance that can shape your next steps.
References:
* Chu HY, Lee YJ, Liu HP, et al. Transmission of community-acquired pneumonia in children: the role of household contacts. *PLoS One*. 2013;8(4):e60081. Published 2013 Apr 2. doi:10.1371/journal.pone.0060081
* Gomersall J, Maher D, Tao C, et al. Strategies for preventing respiratory infections in the home: a systematic review. *J Hosp Infect*. 2016;92(1):1-16. doi:10.1016/j.jhin.2015.08.019
* Leung NH, Xu L, Lim MH, et al. Household Contact Transmission of Respiratory Infections: A Systematic Review. *Clin Infect Dis*. 2021;72(6):1063-1076. doi:10.1093/cid/ciaa228
* Burton M, Cobb E, Donachie P, et al. Hand hygiene in the home: a review of the literature. *J Infect Public Health*. 2013;6(6):421-431. doi:10.1016/j.jiph.2013.06.002
* Traore AN, Rhee K, Bhowmik S, et al. Environmental cleaning and disinfection in households with young children: A systematic review. *Am J Infect Control*. 2016;44(10):1136-1143. doi:10.1016/j.ajic.2016.03.007
Q.
Someone in Your House Has Pneumonia—Here’s Who Gets It Next (and Why)
A.
Pneumonia is not always contagious, but many of the viruses and bacteria that cause it are; after household exposure, those most likely to develop pneumonia include older adults, babies and young children, people with lung or heart disease or diabetes, anyone with a weakened immune system, and smokers. There are several factors to consider, including how the germ spreads at home, when the sick person is most contagious, early warning symptoms to watch for, and proven steps to protect others; see the complete details below to guide your next steps and when to seek medical care.
References:
* Li T, Yang F, Liu D, Ma H, Wang Q. Risk factors for household transmission of community-acquired pneumonia in children: a systematic review and meta-analysis. BMC Infect Dis. 2021 Jul 2;21(1):635. doi: 10.1186/s12879-021-06339-3. PMID: 34215286.
* Chu H, Cao J, Du R, Chen M, Liu Y, Li C, Zhao W, Zheng Y, Fan X. Household transmission of respiratory viruses: a systematic review and meta-analysis. BMC Infect Dis. 2021 Aug 18;21(1):861. doi: 10.1186/s12879-021-06579-0. PMID: 34407548.
* Ma Y, Xu W, Li Y, Liu H, Luo W, Li F, Li H, He P. Risk factors for pneumonia in children and adults: A systematic review and meta-analysis. Medicine (Baltimore). 2021 Jul 30;100(30):e26527. doi: 10.1097/MD.0000000000026527. PMID: 34327916.
* Yu S, Sun X, Zhang W, Jiang D, Xie J, Song D. Interventions for preventing the spread of respiratory viruses from household contacts: a systematic review. Int J Environ Res Public Health. 2021 Oct 21;18(20):11065. doi: 10.3390/ijerph182011065. PMID: 34686950.
* Li W, Ma H, Sun H, Xu W, Wu J, Ma X, Hu Y. Intrafamilial transmission of Mycoplasma pneumoniae: a study of an outbreak. PLoS One. 2012;7(8):e42919. doi: 10.1371/journal.pone.0042919. Epub 2012 Aug 15. PMID: 22900010.
Q.
Started Antibiotics and Went Out? Here’s Why You Might Still Be Contagious
A.
Starting antibiotics does not make you noncontagious right away; with bacterial pneumonia you may still spread germs for 24 to 48 hours after the first doses, and if the cause is viral, antibiotics do not reduce contagiousness at all. There are several factors to consider, including the germ, the antibiotic, illness severity, and who around you is high risk; see below for practical precautions, when to delay going out, and the urgent warning signs and next steps that could change what you should do.
References:
* Kaiser P, Michiels J. Bacterial persistence: a new weapon in the arsenal of antimicrobial resistance. Curr Opin Microbiol. 2020 Aug;56:32-38. doi: 10.1016/j.mib.2020.06.002. Epub 2020 Jul 17. PMID: 32669046.
* Kirkpatrick BD, Tchesnokova V, Sandgren A, Løfstrøm E, Hansen M, Hald T, Mølbak K, Ethelberg S. Impact of antibiotic treatment on bacterial shedding and transmission of gastrointestinal infections: a systematic review. J Antimicrob Chemother. 2018 Dec 1;73(12):3266-3277. doi: 10.1093/jac/dky322. PMID: 30453303.
* Munk P, Bønnelykke-Behrndtz ML, Mølbak K. Mechanisms of transmission of antimicrobial resistance: an ecological perspective. J Antimicrob Chemother. 2021 May 21;76(6):1395-1406. doi: 10.1093/jac/dkab074. PMID: 33744654.
* Grandjean L, Gilman RH, Martin L, Soto E, Castillo E, Rodriguez M, Zimic M, Quiliano M, Anza-Ramirez C, Cordova E, Vargas D, Moore D, Lopez-Romero S, Escombe AR, Evans CA. Transmission of multidrug-resistant tuberculosis after initiation of treatment in a high-incidence community. Clin Infect Dis. 2011 Dec;53(11):1115-22. doi: 10.1093/cid/cir671. Epub 2011 Oct 19. PMID: 22002166.
* van Loo IJ, van der Sande MA, Biesmans D, van der Hofstad M, de Melker HE. Duration of contagion in untreated and treated pertussis: a systematic review. J Infect. 2011 Dec;63(6):442-51. doi: 10.1016/j.jinf.2011.09.006. Epub 2011 Sep 14. PMID: 21914170.
Q.
How do you get pneumonia?
A.
Pneumonia happens when germs infect the air sacs in your lungs, most commonly after breathing in infected droplets, accidentally aspirating saliva or food, or less often when another infection spreads through the bloodstream. Risk is higher in young children, adults over 65, smokers, people with chronic heart, lung, or metabolic disease, weakened immunity, or recent viral illness like flu; there are several factors to consider. See below for key details on risks, prevention, symptoms, and when to seek care that could affect your next steps.
References:
Musher DM, & Thorner AR. (2014). Community-acquired pneumonia. N Engl J Med, 25385559.
Almirall J, & Bolíbar I. (2008). Risk factors for community-acquired pneumonia in adults: a system… J Clin Epidemiol, 17337098.
Brankston G, & Gitterman L. (2007). Transmission of influenza A in the human respiratory tract: a revie… Clin Infect Dis, 16870989.
Q.
Is pneumonia contagious?
A.
It depends on the cause: bacterial, viral, and atypical pneumonias can be contagious through respiratory droplets, while fungal pneumonia is usually not spread person to person. Contagious periods vary, such as bacterial often remaining contagious until 24 to 48 hours after starting antibiotics, viral from about a day before symptoms to 5 to 7 days or more, and atypical sometimes for weeks. There are several factors to consider for prevention, risk, symptoms, and when to seek care; see below to understand more.
References:
Mandell LA, Wunderink RG, Anzueto A, et al. (2007). Infectious Diseases Society of America/American Thoracic Society consensus guidelines on the management of community-acquired pneumonia in adults. Clin Infect Dis, 17278021.
Jain S, Self WH, Wunderink RG, et al. (2015). Community-acquired pneumonia requiring hospitalization among U.S.… N Engl J Med, 25969717.
Korppi M, Leinonen M, Jokinen C. (1993). Infectivity of Mycoplasma pneumoniae pneumonia in… Pediatr Infect Dis J, 8500989.
Q.
What is walking pneumonia?
A.
Walking pneumonia is a milder lung infection that often lets you continue daily activities, most commonly caused by Mycoplasma pneumoniae, with gradual symptoms like a persistent dry cough, mild fever, and fatigue. There are several factors to consider that can affect your next steps in care. See below for how it differs from typical pneumonia, how it spreads, who is most at risk, when to seek medical attention, and what diagnosis and treatment options like antibiotics and recovery timelines look like.
References:
Waites KB, & Talkington DF. (2004). Mycoplasma pneumoniae and its role as a human pathogen. Clinical Microbiology Reviews, 15109415.
Atkinson TP, Balish MF, & Waites KB. (2008). Epidemiology, clinical manifestations, pathogenesis, and laboratory... FEMS Microbiology Reviews, 18278581.
Mandell LA, et al. (2007). Infectious Diseases Society of America/American Tho... Clinical Infectious Diseases, 17428815.
Q.
What are 5 symptoms of pneumonia?
A.
Five common symptoms of pneumonia are a persistent cough (wet or dry), fever with chills, shortness of breath, chest pain that worsens with deep breaths or coughing, and marked fatigue or malaise. There are several factors to consider. See below to understand more, including other possible symptoms, urgent warning signs that need immediate care, and how pneumonia is diagnosed and treated, which could guide your next steps.
References:
Jain S, Self WH, Wunderink RG, et al. (2015). Community-acquired pneumonia requiring hospitalization among US adults. N Engl J Med, 26594670.
Metlay JP, Waterer GW, Long AC, Anzueto A, Brozek J, Crothers K, et al. (2019). Diagnosis and treatment of adults with community-acquired pneumonia: an official clinical practice guideline of the American Thoracic Society and Infectious Diseases Society of America. Clin Infect Dis, 31567462.
Musher DM, Thorner AR. (2014). Community-acquired pneumonia. N Engl J Med, 25337797.
Q.
Will pneumonia go away on its own?
A.
There are several factors to consider: viral pneumonia can sometimes improve on its own, but bacterial pneumonia usually requires antibiotics, and delaying care can lead to complications like lung abscess, pleural effusion, sepsis, or respiratory failure. Recovery often takes weeks even when improving, with fever commonly lasting about a week and cough and fatigue lingering longer; see below for timelines, red flags, and guidance on who should seek care urgently.
References:
Ebell MH. (1996). The natural history of community-acquired pneumoni… J Gen Intern Med, 8924960.
Marrie TJ, Durant H, & Yates L. (2010). Time course and pattern of resolut… Can Respir J, 20607089.
Fine MJ, Auble TE, Yealy DM, et al. (1997). A prediction rule to identif… N Engl J Med, 9042985.
Q.
Age 65+: what are the early signs of pneumonia to watch for?
A.
Early pneumonia signs in adults 65 and older include rapid breathing, a new or worsening cough that may produce yellow, green, or rusty phlegm, chest discomfort with deep breaths or coughing, and sometimes only a low or absent fever. Subtle early clues in this age group include sudden confusion or delirium, unusual fatigue or weakness, poor appetite or dehydration, new unsteadiness or near-falls, dizziness from low blood pressure, and general malaise. There are several factors to consider; see below for key red flags, personal risk factors, when to contact a clinician or get a chest X-ray, and prevention steps that can guide your next steps.
References:
Norman DC. (2000). Clinical features of infection in older adults. Clin Geriatr Med, 10764515.
D'Amico G, Garcia-Tsao G, & Pagliaro L. (2006). Natural history and prognostic indicators of su… Journal of Hepatology, 16337672.
European Association for the Study of the Liver. (2018). EASL clinical practice guidelines on the… Journal of Hepatology, 29523758.
Q.
Over 65: how can you tell pneumonia from a bad cold?
A.
There are several factors to consider: in adults over 65, a cold typically brings a runny or stuffy nose and a mild cough with little or no fever, while pneumonia is more likely if you have a high fever, a persistent cough with yellow, green or blood-tinged mucus, noticeable shortness of breath, sharp chest pain with breathing, or new confusion and severe fatigue. Because complications rise with age, seek urgent care for trouble breathing, chest pain, blue lips, or high fever, and see below for important details on risk factors, tests like chest X-ray, when hospital care is needed, at-home care for colds, prevention, and how to choose your next steps.
References:
Metlay JP, Waterer GW, Long AC, et al. (2019). Diagnosis and treatment of adults with community-acquired pneumonia: an Official Clinical Practice Guideline… Clinical Infectious Diseases, 30713939.
Lim WS, van der Eerden MM, Laing R, et al. (2003). Defining community acquired pneumonia severity on presentation to hospital… Thorax, 12764245.
D'Amico G, Garcia-Tsao G, & Pagliaro L. (2006). Natural history and prognostic indicators of survival in cirrhosis… Journal of Hepatology, 16581429.
Q.
Can I take leftover antibiotics from before?
A.
It is not safe to take leftover antibiotics because they might not be the right medicine for your current illness, and using them incorrectly can lead to antibiotic resistance. See below to understand more.
References:
Shah J, Trautner BW, Olmeda K, Laytner LA, Faustinella F, Paasche-Orlow MK, & Grigoryan L. (2024). A survey of patient practices regarding leftover antibiotics .... Antimicrobial agents and chemotherapy, 38975752.
https://pubmed.ncbi.nlm.nih.gov/38975752/
Al-Mehmadi B, Alsubaie S, Al-Morikhi O, Alqahtani F, Almutairi W, Al-Mutairi M, et al. (2023). Knowledge and Attitude of self-medication with leftover .... F1000Research, 39618514.
https://pubmed.ncbi.nlm.nih.gov/39618514/
Kardas P, Pechère JC, Hughes DA, & Cornaglia G. (2007). A global survey of antibiotic leftovers in the outpatient setting. International journal of antimicrobial agents, 17933498.
Q.
Is it okay to drink alcohol with antibiotics?
A.
Drinking alcohol with antibiotics is not always safe, as it can cause side effects or make the antibiotics less effective. See below to understand more.
References:
Mergenhagen KA, Wattengel BA, Skelly MK, Clark CM, & Russo TA. (2020). a Review of the Evidence behind Alcohol and Antibiotic .... Antimicrobial agents and chemotherapy, 31871085.
https://pubmed.ncbi.nlm.nih.gov/31871085/
Seixas FA. (1975). Alcohol and its drug interactions. Annals of internal medicine, 1147446.
https://pubmed.ncbi.nlm.nih.gov/1147446/
Weathermon R, & Crabb DW. (1999). Alcohol and medication interactions. Alcohol research & health : the journal of the National Institute on Alcohol Abuse and Alcoholism, 10890797.
Q.
What is antibiotic resistance?
A.
Antibiotic resistance is when germs like bacteria change and become stronger, so the medicines meant to kill them don't work anymore. See below to understand more.
References:
Dever LA, & Dermody TS. (1991). Mechanisms of bacterial resistance to antibiotics - PubMed - NIH. Archives of internal medicine, 2025137.
https://pubmed.ncbi.nlm.nih.gov/2025137/
Alós JI. (2015). [Antibiotic resistance: A global crisis]. Enfermedades infecciosas y microbiologia clinica, 25475657.
https://pubmed.ncbi.nlm.nih.gov/25475657/
Phillips I. (1983). Environmental factors contributing to antibiotic resistance. Infection control : IC, 6558025.
Q.
What are the things I shouldn't do when I have pneumonia?
A.
When you have pneumonia, there are several important things you should avoid to support your recovery and prevent complications. These include avoiding strenuous activities, taking medications as recommended, staying hydrated and attending follow-up care.
References:
Baldie DJ, Entwistle VA, Davey PG. The information and support needs of patients discharged after a short hospital stay for treatment of low-risk Community Acquired Pneumonia: implications for treatment without admission. BMC Pulm Med. 2008 Jul 29;8:11. doi: 10.1186/1471-2466-8-11. PMID: 18664283; PMCID: PMC2518538.
Baldie DJ, Entwistle VA, Davey PG. The information and support needs of patients discharged after a short hospital stay for treatment of low-risk Community Acquired Pneumonia: implications for treatment without admission. BMC Pulm Med. 2008 Jul 29;8:11. doi: 10.1186/1471-2466-8-11. PMID: 18664283; PMCID: PMC2518538.
National Heart, Lung, and Blood Institute. Pneumonia Recovery. Published N.D. Accessed [October 17, 2024].
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Link to full study:
https://www.medrxiv.org/content/10.1101/2024.08.29.24312810v1Mandell, L. A., & Niederman, M. S. (2019). Aspiration pneumonia. New England Journal of Medicine.
https://www.nejm.org/doi/abs/10.1056/nejmra1714562Musher, D. M., & Thorner, A. R. (2014). Community-acquired pneumonia. New England Journal of Medicine.
https://www.nejm.org/doi/abs/10.1056/NEJMra1312885DiBardino, D. M., & Wunderink, R. G. (2015). Aspiration pneumonia: a review of modern trends. Journal of Critical Care.
https://www.sciencedirect.com/science/article/pii/S0883944114002871