X
Table of contents

Pneumonia

Feel like sharing?

What is pneumonia?

Pneumonia is a lung infection, usually caused by bacteria or viruses. If you have pneumonia, you may experience a bad cough, a fever and difficulty breathing. Pneumonia is most likely to develop after having a cold or flu.

Each lung is filled with thousands of small airways that branch into tiny air sacs, which allow oxygen from the air we breathe to enter the blood. If you have pneumonia, these air sacs in the lung fill with fluid and mucus, which interferes with the breathing process.

Pneumonia can affect people of any age, but is more common in young children, the elderly and people with weak immune systems. Treatment for pneumonia depends on the severity and the specific cause, but includes a combination of medication and self-care treatments, including getting plenty of rest and drinking lots of fluids.

Causes

Pneumonia is usually caused by an infection with bacteria or viruses that have been inhaled into the lungs. Your body's immune system then sends white blood cells to attack the germs that are causing the infection. This causes the air sacs in the lung, called alveoli, to become filled with fluid and mucus, which can cause difficulty breathing.

Pneumonia causes alveoli in the lung to fill with fluid and mucus. 

Risk factors

Anyone can get pneumonia, but young children and people over the age of 65 have a higher risk of developing the condition. Some other factors that can increase your risk of getting pneumonia include:

  • Having a weak immune system, which can occur in people who have HIV/AIDS;
  • Taking anti-inflammatory medications, such as corticosteroids;
  • Other lung conditions, such as asthma, chronic obstructive pulmonary disease (COPD) or bronchiectasis, and;
  • Smoking, which can damage your lungs and make it harder for your immune system to prevent lung infections.

Types

Bacterial pneumonia

Bacterial pneumonia is caused by bacteria. The most common type of bacteria that cause this form of pneumonia is Streptococcus pneumoniae. Other bacteria that cause pneumonia include Klebsiella pneumoniae and Haemophilus influenzae, which are more common in people with weak immune systems.

Viral pneumonia

Viral pneumonia is caused by infection with a virus. Some of the common types of viruses that cause this type of pneumonia include the influenza virus (which also causes the flu), adenoviruses and rhinoviruses (which cause colds).

Fungal pneumonia

Fungal pneumonia is a rare type of pneumonia caused by a fungal infection. It is more common in people with weak immune systems, which includes people who are taking medications to suppress their immune system and people who have HIV/AIDS. Some of the common causes of fungal infections that can lead to this type of pneumonia include Histoplasmosis, Coccidiomycosis, Blastomycosis, Aspergillosis and Cryptococcosis.

Parasitic pneumonia

Although uncommon, some types of parasites can also cause pneumonia. They can enter the body through direct contact with the skin, through the mouth, or through an insect bite. Some of the parasites that can cause pneumonia include Toxoplasma gondii, Strongyloides stercoralis, Ascarislumbricoide and Plasmodium malariae.

Signs and symptoms

If you have pneumonia you may experience some of these symptoms:

Methods for diagnosis

Working out if you have pneumonia can be hard, because some symptoms are very similar to a common cold or flu. If your doctor suspects that you have pneumonia, a diagnosis will usually be made based on the results from a physical exam, an X-ray of your chest and laboratory test results.

Physical examination

During a physical examination, your doctor may use a stethoscope to listen to your lungs for crackles and other unusual sounds when you breathe. Gently tapping on the chest, by your doctor, may elicit dullness that can also suggest pneumonia.

X-ray

Your doctor may take an X-ray of your chest to confirm if you have pneumonia and determine which part of your lungs are affected.

Laboratory tests

A blood test or a sample of sputum that is coughed up may be used to help work out whether the cause of your pneumonia is bacterial, viral or fungal.

Types of treatment

Pneumonia is usually treated with a combination of medication and self care. Your specific treatment will depend on how bad your condition is and what is causing it. If you have very severe symptoms or have a weak immune system, you may need to go to hospital.

Self care

For mild cases of pneumonia, self-care treatments may help recovery. These include getting plenty of rest, drinking lots of fluids and avoiding cigarette smoke.

Medications

Mild bacterial pneumonia can be treated with oral antibiotics including amoxicillin and clavulanic acid, doxycycline or roxithromycin. Very severe bacterial pneumonia may need to be treated in hospital with intravenous antibiotics, such as benzylpenicillin.

Mild viral pneumonia is usually treated with self care. Over-the-counter pain-relief medications such as acetaminophen, or anti-inflammatory medications such as ibuprofen, might help in reducing some of the symptoms of pneumonia.

Fungal pneumonia is usually treated with antifungal medications.

Prognosis

If left untreated, pneumonia can be life-threatening, but most cases will get better with a combination of proper medical treatment, rest, plenty of fluids and a healthy diet to boost your immune system. You are more likely to recover quickly if your condition is diagnosed and treated early. Most cases of pneumonia will start to improve within a week, but it will often take a few weeks for all symptoms to disappear.

The risk of developing complications from pneumonia is higher in people over the age of 65 and in young children. People who have long-term diseases such as chronic obstructive pulmonary disease (COPD) and HIV/AIDS have a higher chance of developing complications of pneumonia.

Prevention

Avoiding people with a cold or flu and washing your hands before eating, handling food, or touching your mouth or nose can reduce the spread of the bacteria and viruses that commonly cause pneumonia. Other ways to reduce the risk of pneumonia include:

Vaccination

There are two vaccines available that may protect you from the most common bacteria that cause pneumonia. These are the pneumococcal conjugate vaccine, which is usually given to children as part of the childhood immunization program, and the pneumococcal polysaccharide vaccine, which is generally given to people who have an increased risk of developing pneumonia. These vaccinations may not always prevent people from developing pneumonia, but they may stop the condition from becoming very serious.

A yearly vaccination can help prevent pneumonia. 

Avoiding smoking

Smoking causes damage to the lungs and can make you more likely to develop lung infections. Avoiding and quitting smoking can reduce your chance of getting pneumonia.

References

  1. link here
  2. Treatment: John Murtaghs General Practice

10 Most frequently asked questions (FAQs)

What is pneumonia?
Pneumonia is an inflammation of the lung tissue. It is usually caused by an infection with bacteria or viruses. The symptoms of pneumonia include a cough that produces lots of mucus; fever; tiredness, and difficulty breathing.
What causes pneumonia?
Pneumonia is usually caused by an infection with bacteria or viruses that have been inhaled into the lungs. Your body's immune system then sends white blood cells to attack the germs that are causing the infection. This causes the air sacs in the lung to become filled with fluid and mucus, which can cause difficulty breathing.
Who gets pneumonia?
Anyone can get pneumonia, but young children and people over 65 years of age have a higher risk of developing the condition. People who have a weak immune system, including people with HIV/AIDS, people who are taking medications to reduce the activity of their immune system and people who smoke also have a higher risk of developing pneumonia.
Can pneumonia be fatal?
Pneumonia can sometimes be fatal. People who are elderly, have complicated medical problems, have a weak immune system or have a very aggressive organism that is causing their pneumonia are at risk of dying from pneumonia. Pneumonia that is left untreated can become life-threatening.
How is pneumonia diagnosed?
A doctor will diagnose pneumonia on the basis of a physical exam and test results. During a physical examination a doctor may use a stethoscope to listen for crackles or abnormal sounds caused by breathing. An X-ray can be used to confirm pneumonia and work out which part of the lungs are affected. A sputum sample can confirm the organism causing the pneumonia and the most suitable antibiotics or antifungals needed to treat them.
How is pneumonia treated?
Pneumonia is usually treated with a combination of medication and self-care. For mild cases, self-care treatments such as getting plenty of rest and drinking lots of fluids are recommended. Bacterial pneumonia is usually treated with antibiotics; antifungal medications are used to treat fungal pneumonia. Severe cases of pneumonia may need to be treated in hospital.
How long does it take to recover from pneumonia?
The length of time it takes to recover from pneumonia depends on what has caused it and the strength of the immune system of the person affected. Most cases will start to improve within a week, but it will often take a few weeks for all of the symptoms to disappear.
Is pneumonia contagious?
Pneumonia can be contagious. Some of the viruses and bacteria that cause pneumonia are more contagious than others. People with a weak immune system are more likely to catch pneumonia from someone who already has it. But in most cases, if the germs that cause pneumonia are passed on to someone, they create a milder infection, such as the common cold.
How can I tell the difference between a cough and pneumonia?
A physical examination by a doctor will help determine the difference between pneumonia and a cough. A chest X-ray and laboratory tests of blood or sputum samples can also help to diagnose pneumonia.
Can pneumonia be prevented?
There are several things that can be done to reduce the risk of getting pneumonia. There are several vaccines available to protect against some types of bacteria that cause pneumonia. Avoiding cigarette smoke and people with a cold or flu and washing your hands before eating or handling food, can reduce the spread of the bacteria and viruses that commonly cause pneumonia.

Related topics

Bronchitis

Bronchitis is a common condition that occurs when the lungs become inflamed. It causes coughing and difficult breathing. Acute bronchitis refers to the short-term type, and may occur in the aftermath of cold or flu. While the cough may be severe, it typically lasts for only a few weeks.

Cough

Coughing is your body's way of getting rid of any foreign material or mucus in your lungs. Coughing can be a response to breathing in dust or fumes that irritate the nerve endings in the airways, or can be a symptom of a medical problem, such as a lung infection caused by bacteria or a virus, or a long-term lung disease such as asthma.

Bronchiectasis

Bronchiectasis is a lung disease in which the airways (bronchi) become damaged and scarred by repeated lung infections. It can cause a build-up of mucus in the airways, leading to persistent coughing and difficulty breathing.

The flu (influenza)

The flu, or influenza, is a common viral infection, which causes fevers, headache, coughing and muscle aches. It is different to the common cold, which usually has relatively milder symptoms. Rarely, complications can occur with the elderly, children and people with weakened immune systems.

About this article

Title: Pneumonia

Author: Dr Joanne Van der Velden PhD, BSc (Hons)

First Published: 18 Sep 2014

Last reviewed: 17 Jan 2022

Category: Information on Pneumonia

Average rating: 4.4 out of 5 (1556 votes)

Processing your vote now...

Sorry your vote failed to process.

Rate this report below.

Feel like sharing?

X

Your privacy

We use cookies to improve our website and service. By continuing to browse this website you accept the use of cookies by us and our partners. If you require more information please read our privacy policy and terms and conditions before proceeding.