Pneumonia

Prior to the invention of antibiotics pneumonia killed one third of its victims, and even today, around 5% of pneumonia patients will die from their illness.

Pneumonia results from an infection which causes the air sacs in the lungs to become inflamed and filled with fluid, causing breathing difficulties. The infection may result from breathing in small airborne droplets containing the infecting organisms. Or, it may result from bacteria or viruses that ordinarily live in the mouth, throat or nose, inadvertently entering the lungs. Usually the immune system can counter these bacteria, viruses or fungi, but if a person is in an already weakened state, pneumonia may develop. In babies and the elderly, the typical symptoms of pneumonia may be absent. Instead there may just be a generalised “illness” and unexplained fever and lethargy.

Types of pneumonia 

Pneumonia can be divided into several different types:

• Bacterial – the main cause is a bacterial infection, often Streptococcus Pneumoniae.  This kind of pneumonia can follow viral pneumonia. Symptoms come on suddenly and include shaking chills, a high fever, shortness of breath and a cough with thick green phlegm. The Pneumovax vaccine is available against Streptococcus Pneumonia and is recommended for the elderly, infants, smokers and people with compromised immunity.
• Viral – A virus is the cause in about 50% of all cases of pneumonia. Onset usually begins with flu-like symptoms such as headache, fever, muscle pain and fatigue. The cough is usually dry or produces scant white mucus.
• Mycoplasma – pneumonia caused by this organism can be quite mild. However, this is a very contagious type of pneumonia and is common in children and young adults.
• Rare forms of pneumonia are caused by fungi, and Pneumocystis carinii – an opportunistic infection that affects people living with AIDS, or people with greatly suppressed immune systems from organ transplant or chemotherapy. Aspiration pneumonia is where food, liquid, chemicals or dust spill into the lungs. This is more likely to occur in debilitated people or those intoxicated by alcohol or drugs who then vomit.

Risk factors for pneumonia

• Old age or babies
• A recent viral infection such as the flu
• Problems swallowing
• Immune suppression from disease or surgery
• Excessive alcohol consumption
• Cigarette smoking
• Hospitalisation
• Injury or surgery where there is prolonged immobilisation.

Diagnosing pneumonia

This is done on the symptoms and signs ie worsening cough and fever and sputum production. These may happen rapidly or be slow in developing. There may be general symptoms of weakness and pain and unwellness. Confirmation is made with a chest xray, blood tests and sputum culture.