Pneumonia Overview

Pneumonia is a form of acute respiratory infection that affects the lungs. When an individual has pneumonia, the alveoli, small air sacs in lungs, are filled with fluid and pus. It makes breathing painful and limits oxygen intake. Pneumonia is a contagious disease.


Pneumonia is a form of acute respiratory infection in one or both lungs. It can be caused by bacteria, viruses, or fungi. These infections are generally spread by direct contact with infected people.

Read this pneumonia guide to learn more about pneumonia disease and how to deal with it.

In this pneumonia medical condition guide, you’ll learn all about Pneumonia, its facts, symptoms, causes & types, prevention, risk factors, classification, diagnosis, treatment & recovery, and its connection with other diseases.

Pneumonia Facts

According to WHO, NIH, and other Pneumonia research centers: –

  • Pneumonia is a contagious disease.
  • While some people are at higher risk than others, anyone can get pneumonia. (see listed risk factors of pneumonia)
  • Pneumonia can have more than 30 different causes.
  • Pneumonia can be very serious and can cause death to people with weak immune systems and other chronic diseases.
  • Good health habits like cleanliness and proper hygiene can fight pneumonia.
  • Around 120 million cases of pediatric pneumonia are seen each year worldwide. (source: National Institutes of Health)
  • Pneumonia is more common than you think. It causes more than a million hospitalizations and more than 50,000 deaths each year. (source: American Lung Association)
  • 15% of all deaths of children under 5 years are caused by Pneumonia. ( reported in 2017) In 2013, it was 29%.
  • The Integrated Global Action Plan for the Prevention and Control of Pneumonia and Diarrhoea (GAPPD), by WHO/UNICEF, aimed to see a drop in deaths from pneumonia to fewer than 3 children in 1000 live births, and from diarrhea to less than 1 in 1000 by 2025. (reported in 2013)

Pneumonia Classification

Pneumonia is classified into 4 groups based on how and where it appeared: –

  • Hospital-acquired pneumonia (HAP) is a serious form of pneumonia that appears during a stay in the hospital.
  • Community-acquired pneumonia (CAP) is the classification of pneumonia that first appears outside of any medical institution like clinic, hospital, or labs.
  • Ventilator-associated pneumonia (VAP) happens to people using a ventilator.
  • Aspiration pneumonia happens upon inhalation of bacterial germs from food, drinks, or saliva.

Pneumonia Causes & Pneumonia Types

Pneumonia can be caused by infectious germs including bacteria, fungi, and viruses.

Based on the cause and condition that lead to pneumonia, there are multiple types of pneumonia: –

Bacterial Pneumonia

These are the bacteria that causes bacterial pneumonia: –

  • Streptococcus pneumoniae bacteria, also known as pneumococcus, cause pneumococcal pneumonia. Pneumococcus bacteria are spread through coughing, sneezing, and close contact with an infected person. (source: Centers for Disease and Control Prevention)
  • Haemophilus influenzae type b (Hib), spreads through close contact with an infected person, coughing, sneezing, and even people who are not sick can have the bacteria in their noses and throats and spread the bacteria. (source: Centers for Disease and Control Prevention)
  • Mycoplasma pneumoniae, also known as Mpneumoniae bacteria, causes ‘walking pneumonia‘ or ‘atypical pneumonia‘ which is a mild infection in the respiratory system. Walking Pneumonia or Atypical Pneumonia is the most common type of bacterial pneumonia. Walking pneumonia is a type of community-acquired pneumonia (CAP).
  • Legionella pneumophila, also known as L. pneumophila, causes a severe pneumonia called Legionnaires disease.

Viral Pneumonia

Viral pneumonia is a mild pneumonia caused by respiratory viruses including: –

  • influenza A: It’s a virus that causes respiratory contagious form of flu infecting nose, throat, and lungs.
  • respiratory syncytial, also known as (sin-SISH-Uhl) or RSV virus, is a virus that causes mild cold-like symptoms. Normally infected person recovers within a week or two. It can be serious for infants and older adults.
  • rhinovirus is an infectious virus that is the predominant cause of the common cold.
  • human parainfluenza virus (HPIV) infection
  • human metapneumovirus (HMPV) infection
  • measles virus causes a highly contagious disease in which you get a runny nose, red eyes, high fever, and cough. Measles may cause pneumonia.
  • chickenpox (varicella-zoster virus)
  • adenoviruses, a group of viruses, cause cold-like symptoms, fever, sore throat, bronchitis, pneumonia, diarrhea, and pink eye (conjunctivitis).
  • 2019’s viral infection can also lead to severe pneumonia and may cause death

Fungal Pneumonia

Pneumonia that people get due to fungi is fungal pneumonia. These are the fungal pneumonia types caused by different fungus: –

  • Pneumocystis pneumonia is caused by Pneumocystis jirovecii yeast-like fungus (previously known as Pneumocystis carinii fungus).
  • Cryptococcal pneumonia is caused by Cryptococcus neoformans (a type of Cryptococcus species). Cryptococcal pneumonia is a fungal infection predominantly in immunosuppressed individuals and rarely in the immunocompetent population. It is caused by the inhalation of fungal spores.
  • Histoplasmosis is a fungal lung infection caused by Histoplasma fungus (a type of histoplasmosis species of fungus)

Pneumonia symptoms

When an individual has Pneumonia, several mild to severe early signs of pneumonia may appear like cough, trouble breathing, and chills. As per American Lung Association, signs and symptoms of pneumonia include: –

  • Cough, which may produce greenish, yellow or even bloody mucus
  • Fever, sweating and shaking chills
  • Nausea and vomiting, especially in small children
  • Shortness of breath, anytime
  • Rapid, shallow breathing
  • Loss of appetite, low energy, and fatigue
  • Sharp or stabbing chest pain that gets worse when you breathe deeply or cough
  • Confusion, especially in older people
  • loss of appetite
  • headaches

Pneumonia in Babies / Infants / Children

Infants may develop no clear symptoms, but sometimes they may: –

  • vomit
  • lack energy
  • trouble drinking
  • trouble eating properly

Pneumonia in children is more common. Pneumonia Symptoms in children under 5 years can be fast breathing and wheezing. A wheeze is a continuous, coarse, whistling sound produced in the respiratory airways during breathing. (source: Wikipedia)

Pneumococcal pneumonia and Haemophilus influenzae is common in children under 5 years.

Pneumonia can be critically dangerous among young children.

Pneumonia Prevention

Pneumonia can be prevented with vaccination and proper hygiene habits.

Pneumonia Vaccines

According to the National Heart, Lung, and Blood Institute, Center for Disease Control, and American Lung Association, these pneumonia vaccines help you prevent getting pneumonia: –

Influenza (flu) Vaccine

Influenza is a common cause of getting pneumonia. Getting the Influenza (flu) vaccine every year to prevent seasonal flu would help in preventing pneumonia.

Pneumococcal Vaccine

Two common pneumococcal vaccines are: –

  • Pneumococcal conjugate vaccine (PCV13)
  • Pneumococcal polysaccharide vaccine (PPSV23)

Pneumococcal conjugate vaccine (PCV13) is recommended for: –

  • All children younger than 2 years old
  • People 2 years or older with certain medical conditions
  • In addition, adults 65 years or older may discuss and decide, with their clinician, to receive PCV13.

Pneumococcal polysaccharide vaccine (PPSV23) is recommended for: –

  • All adults 65 years or older
  • People 2 through 64 years old with certain medical conditions
  • Adults 19 through 64 years old who smoke cigarettes

HIB Vaccine

The Hib vaccine is given to children to help prevent pneumonia and meningitis disease. Haemophilus influenzae type b (Hib) is recommended for children under 5 years of age. The vaccine often is given to infants starting at two months of age.

More Bacterial Vaccines for Pneumonia

Besides the HIB vaccine, pneumococcal vaccine, and influenza vaccine to prevent pneumonia, there may be other bacterial infection prevention vaccines.

Synagis (palivizumab) dose, which is given to some children under 2 years to prevent pneumonia caused by RSV virus. Must consult your doctor to learn which vaccine and drug is appropriate for you and for your children.

Hygiene Habits to Prevent Pneumonia

Vaccines are helpful but, self-care and hygiene habits are always important such as: –

Washing your hands

Wash your hands, nose, and mouth frequently. Wash hands after diapering, sneezing, coughing, cleaning the nose, and similar activities. Wash your hands even before eating and preparing food.

Avoid Smoking

Tobacco damages your lungs’ ability to filter out and defend infectious germs. Smokers are considered one of the high-risk groups that are encouraged to get the pneumococcal vaccine.

Strengthen your Immunity

Keep your immunity strong by these simple things to prevent and recover fast from seasonal diseases: –

Pneumonia Diagnosis

Doctors diagnose pneumonia based on your medical history and asking questions related to pneumonia symptoms.

Medical History

Your doctor might ask about your recent traveling, hobbies, exposure to animals, contact with sick people, and more. Your doctor may also inquire about any smoking habit, alcohol intake, any medicines you took, and/or existing vaccinations.

Physical Exam

Using a stethoscope, a doctor listens to the lungs. If you’ve developed pneumonia symptoms, your lungs may make crackling, bubbling, & rumbling sounds when you inhale. Your doctor also may hear wheezing. Your doctor may find it hard to hear sounds of breathing in some areas of your chest.

Pneumonia Diagnosis Tests

Doctors recommend one or more pneumonia diagnosis tests including: –

  • Blood tests for pneumonia are recommended to confirm the infection and to identify the infectious agent or germ which is causing you pneumonia illness.
  • Chest X-ray for pneumonia is recommended to look for the exact location and inflammation details in your lungs.
  • Sputum test for pneumonia is recommended to look for the source of the infection. It is taken with a sample of your mucus after a deep cough.
  • Pulse oximetry test for pneumonia is recommended to measure the oxygen level in blood as pneumonia can stop your lungs from passing enough oxygen into your bloodstream.

In the case of high-risk patients including hospitalized patients, patients with other chronic diseases, some additional tests for pneumonia may be required including: –

  • CT scan of the chest to get a better view of the lungs and look for abscesses or other complications.
  • Arterial blood gas test, to measure the amount of oxygen in a blood sample taken from an artery, usually in your wrist. This is more accurate than the simpler pulse oximetry.
  • Pleural fluid culture, which removes a small amount of fluid from around tissues that surround the lung, to analyze and identify bacteria causing the pneumonia.
  • Bronchoscopy, a procedure used to look into the lungs’ airways. If you are hospitalized and your treatment is not working well, doctors may want to see whether something else is affecting your airways, such as a blockage. They may also take fluid samples or a biopsy of lung tissue.

Pneumonia Treatment

Treating pneumonia after diagnosis depends on your diagnosed pneumonia type, condition, age, and severity. Your doctor may prepare a treatment plan which shall be followed throughout your recovery from pneumonia infection. Treatment plans help to reduce recovery complications.

Pneumonia Prescribed Medication

If you’re infected with bacterial pneumonia, then your doctor may prescribe you antibiotics to remove the infectious germs.

It is very important to continue taking the prescribed pneumonia medicine until it is fully gone. If you stop in midway, even though you start feeling better, you’re are high-risk of getting pneumonia back.

If you have viral pneumonia, your doctor may prescribe an antiviral medication to treat it.

Pneumonia Home Medication

Mild pneumonia can be treated at home by following these steps as recommended by Lung Association: –

  • Drink plenty of fluids to help loosen secretions and bring up phlegm.
  • Do not take cough medicines without first talking to your doctor. Coughing is one way your body works to get rid of an infection. If your cough is preventing you from getting the rest you need, ask your doctor about steps you can take to get relief.
  • Drink warm beverages, take steamy baths and use a humidifier to help open your airways and ease your breathing. Contact your doctor right away if your breathing gets worse instead of better over time.
  • Stay away from smoke to let your lungs heal. This includes smoking, secondhand smoke and wood smoke. Talk to your doctor if you are a smoker and are having trouble staying smokefree while you recover. This would be a good time to think about quitting for good.
  • Get lots of rest. You may need to stay in bed for a while. Get as much help as you can with meal preparation and household chores until you are feeling stronger. It is important not to overdo daily activities until you are fully recovered.

Hospitalization in Pneumonia

Some people may develop severe pneumonia and need to be hospitalized. Keeping in contact with doctor always help to understand your pneumonia recovery stage.

For some patients that have serious health conditions already are likely to get hospitalized in pneumonia.

If your pneumonia is so severe that you are treated in the hospital, you may be given intravenous fluids and antibiotics, as well as oxygen therapy, and possibly other breathing treatments.

Pneumonia Risk Factors

Many factors like age, cause, medical history, and environment can cause getting severe pneumonia and other complications.

Infants who are two years old or younger have a weak immune system and are more suspected to get pneumonia.

As pneumonia is a contagious infection, people around you at home may also develop pneumonia symptoms.

Some people with weak immunity, older adults, young children, and who’ve already other medical problems develop serious complications in pneumonia treatment like: –

  • respiratory failure and acute respiratory failure called Acute respiratory distress syndrome (ARDS)
  • an uncontrolled inflammation in the whole body called sepsis
  • Lung abscesses when pockets of pus form inside or around the lung

Pneumonia connection with other diseases

Pneumonia being a contagious disease may have connections with other similar diseases.

Pneumonia vs. Influenza

Influenza is a form of contagious flu that infects the nose, throat, and lungs. Influenza is a common cause of pneumonia which is the inflammation (a serious infection) of the lungs.

Pneumonia vs. bronchitis

Pneumonia is an inflammation infection in air sacs in the lungs while bronchitis is the inflammation of your bronchial tubes.

Getting pneumonia can be serious. Are you feeling similar symptoms or already experienced pneumonia? Share your thoughts in comments or get connected with other community at @exploreitdaily

You can also join our Exploreitdaily Facebook community to get the most out of our helpful health topic guides for you and your family.