What is Pneumonia?
Pneumonia is a type of infection of the lungs caused by either viruses, bacteria or fungi. It can affect one or both lungs and causes the air sacs (alveoli) to fill with pus or fluid.
This condition can affect people of all ages. It is the most prevalent infectious cause of death in children under the age of five worldwide. It is also a leading cause of hospitalization of both adults and children in the US. (1, 2)
There are a number of factors which determine how serious pneumonia is. These include age, general health and the type of germ responsible for the lung infection.
The symptoms of this condition can vary from mild to very severe. Common symptoms include:
Coughing is one of the main symptoms of pneumonia. The cough can be dry and tickly, or productive. The phlegm resulting from a productive cough will be thick, green, brown or yellow in color and can be stained with blood. (3)
Pneumonia can make it difficult for a person to breathe as easily as they would normally. Breathing might be shallow and rapid, with an inability to fully inflate the lungs.
It might also be hard to catch your breath when doing normal activities, or even when resting. (4)
Fever and Chills
The rate at which the heart beats might increase and become rapid. (7)
Individuals might feel unwell in general. If they have recently suffered from a cold or flu, they might suddenly feel much worse. (8)
Loss of Appetite
There are other less common symptoms which might be experienced by some people. These include headaches, fatigue, coughing up blood, wheezing, nausea and vomiting and joint or muscle pain. Elderly people, in particular, might feel disoriented and confused. (10)
While many cases of pneumonia can be treated successfully there are occasions when complications can occur. These include:
Bacteremia and Septic Shock
Bacteremia happens when bacteria at the site of the initial infection enters the bloodstream, which can, in turn, lead to septic shock. This is a reaction in the body which reduces blood pressure and the flow of blood to tissues and organs.
This can lead to damage and failure of major organs, and is potentially fatal. (11)
Pus might collect in the cavities of the lungs and in places where they are inflamed. These can be treated with antibiotics, or might need surgery to drain them. (12)
Pleural Effusions, Pleurisy and Empyema
Two thin layers of tissue form a membrane around the outside of the lungs, and line the chest cavity. Called the pleura, these two layers contain fluid which allows them to slide against each other when we breathe.
Pleurisy is a condition which occurs when these layers become inflamed or irritated. It causes sharp pain when the lungs are inflated on breathing in.
Pleural effusions describe a build up of fluid in the space between the two layers. Should this fluid become infected it is called empyema.
Pneumonia can also lead to kidney failure or respiratory failure. (15)
There are no stages associated with this condition, however it can classified in three different ways. By the type of germ causing infection, by the place the infection was contracted, and by how it was acquired.
Types of Germ Generated Pneumonia
This type of pneumonia can happen on its own or following a viral infection such as a cold or flu. It generally affects one lung, and is referred to as lobar pneumonia.
This common type of pneumonia found in adults can be caused by several different bacteria.
The bacteria which is most frequently responsible for pneumonia in the US is streptococcus pneumoniae (pneumococcus bacteria).
Other bacteria which could be found, referred to as atypical pneumonia, include:
Legionella pneumophila, or Legionnaires disease, is linked to pneumonia contracted from exposure to water infected with this bacteria. It can be contracted from swimming pools, cooling towers, air conditioning and water systems in buildings, water fountains and spa’s. (16)
Mycoplasma pneumoniae is more prevalent in younger people, generally below 40 years old. Working or living in close quarters with others, like homeless shelters, prisons or schools can place a person at higher risk of developing this type of pneumonia.
While often mild and responding well to antibiotic treatment, this pneumonia can also be serious.
Chlamydia pneumoniae is more common in the older generation, developing in people between 65 and 79 years old. This type of pneumonia is not seasonal and often mild. (17)
Any viral infection of the respiratory tract can lead to the development of pneumonia. The most common one affecting adults is the flu virus.
Respiratory syncytial virus (RSV) commonly causes pneumonia in infants.
Other viruses like the common cold (rhinovirus), human metapneumovirus (HMPV) and human parainfluenza virus (HPIV) also cause pneumonia.
Viral pneumonia will normally resolve of its own accord in up to three weeks. However, it can also be serious. It might leave a person more vulnerable to bacterial pneumonia. (18)
A serious fungal infection caused by pneumocystis jirovecii is called pneumocystis pneumonia. People who have weak immune systems are susceptible. This weakened immunity might be due to long term use of medicines to treat conditions like cancer, or who have HIV.
Coccidioidomycosis, histoplasmosis and cryptococcus are fungi found in soil in certain parts of the United States and can cause pneumonia.
Of these cryptococcus is found nationwide, in soil which contains bird droppings. (19)
Types of Location Acquired Pneumonia
Pneumonia can be classified dependent on where the infection was contracted.
Community Acquired Pneumonia (CAP)
This is a pneumonia acquired in the community, not in health care settings or hospitals. Generally caused by pneumococcus bacteria, it is one of the most common types.
This is transmitted by inhaling germs which live in the nose, mouth or throat. (20)
Hospital Acquired Pneumonia (HAP)
This classification applies to people who contract pneumonia while in the hospital for another condition or illness. This is often more serious as individuals are already sick when their pneumonia develops. (21)
Method of Acquiring Pneumonia
This type of pneumonia happens when food, vomit, drink or saliva is inhaled into the lungs. It can occur if your gag reflex is not working properly or if you have issues swallowing. It can also develop if you have used drugs and alcohol excessively.
Aspiration pneumonia can lead to the development of abcesses in the lungs. (22)
Ventilator Associated Pneumonia (VAP)
When being treated in the hospital people might be placed on a ventilator machine to assist their breathing. This can sometimes lead to the development of pneumonia. (23)
The aims of treatment for pneumonia are to clear the infection and prevent the occurrence of complications. Treatment will vary depending on the type of pneumonia, the germ responsible and the severity of the condition.
Community acquired pneumonia is usually successfully treated without the need for hospitalisation.
Treatment for Bacterial Pneumonia
Antibiotic medicines are used to treat this type of pneumonia. The symptoms might begin to clear within a few days. However, if medication is stopped it could return.
It is important that the full course of medication prescribed is taken as directed, even if you feel better beforehand.
Treatment for Viral Pneumonia
Antibiotics are ineffective in the treatment of viruses. Viral Pneumonia will generally improve on its own in between one to three weeks. There are occasions when a doctor might prescribe antiviral medications.
Treatment for Severe Pneumonia
Hospitalization is sometimes required. This might be the case when symptoms are severe or there are complications or risks associated with other health issues.
Oxygen therapy might be given to improve the levels of oxygen in the blood. Antibiotics may be administered intravenously. (24)
In the case of aspiration pneumonia, objects which might have been inhaled will be removed from the lungs. (25)
What is pneumonia? Pneumonia is an infection of the lungs caused by either viruses, bacteria or fungi. It can affect one or both lungs and causes the air sacs (alveoli) to fill with pus or fluid.
What are the signs of pneumonia? Signs of this condition include, coughing, fever, chills, shortness of breath and chest pains.
How do you develop pneumonia? This condition is the result of a bacterial, viral or fungal infection, or inhaling something like food into the lungs.
How are you diagnosed for pneumonia? Full medical history will be obtained and a physical examination will be carried out. Imaging tests might be required as well as tests of sputum, blood and pleural fluid. (26)
What is the best treatment for pneumonia? Treatment will depend on the cause of the pneumonia. Viruses will generally clear of their own accord; bacteria will be treated with antibiotics. Complications and risk factors will also be taken into account.
What are the long term complications of pneumonia? Complications are more prevalent in the very young, very old and people who are already sick. They can include pleurisy, lung abscesses and blood poisoning. (27)
Is pneumonia considered a disability? This condition is not considered a disability, but there are times when a person might qualify for social security benefits. (28)
Is there a cure for pneumonia? Treatments for this condition are often successful.
Is pneumonia considered life threatening? There are occasions when pneumonia can be life threatening, particularly when complications like blood poisoning, abscesses and pleurisy are present.
Pneumonia is a type of infection of the lungs which is viral, bacterial or fungal in origin. It causes a build up of pus in the air sacs impairing their function to oxygenate the body.
The symptoms can make people feel very ill. The good news is there are treatments available to successfully resolve this condition.