Pneumonia

Pneumonia is a mild to life-threatening infection that causes inflammation in the air sacs, alveoli, in your lungs.  Alveoli normally fill with air when a person breathes in. In pneumonia, the alveoli fill with fluid or pus, making it difficult to breathe.

There are around 30 different causes of pneumonia. They grouped by bacterial, viral and fungal infections.

Bacterial pneumonia is the most common cause. Bacterial pneumonia can happen on its own or develop after a viral infection like the flu. Some bacteria that cause pneumonia include

• Streptococcus pneumoniae known as pneumococcal pneumonia. While most people carry this bacterium in their nose or throat without any issues, at risk groups are vulnerable.
• Legionella pneumophila, causes Legionnaires’ disease which is environmentally acquired from contaminated water droplets.
• Burkholderia pseudomallei causes a tropical infection called melioidosis, a form of pneumonia and septicaemia.

Viral pneumonia is responsible for about one-third of pneumonia cases and is caused by a virus that infects the lungs. Viral pneumonia is often mild and goes away on its own within a few weeks.  However, it can require hospitalisation. People who have viral pneumonia are at risk of also getting bacterial pneumonia.  The viruses that can cause pneumonia include

• Influenza viruses
• SARS-CoV-2, the virus, responsible COVID-19
• Respiratory syncytial virus (RSV)
• The common cold virus – Rhinovirus.

Fungal pneumonia is rare and more likely to affect people with chronic health problems or weakened immune systems.

Is pneumonia contagious?

The germs that cause pneumonia are contagious – they are spread by inhaling droplets in the air from a cough or sneeze of an infected person, or from the environment or by contact with surfaces or objects that are contaminated.

Risk factors for developing pneumonia

Risk factors for developing pneumonia include

• Age | Children younger than two years or adults older than 65 years.
• Lifestyle | Smoking, heavy alcohol use and drugs can weaken your immune system.
• Environment | Crowded spaces, exposure to contaminated aerosols, chemicals, air pollutants and toxic fumes.
• Occupation | Some germs that cause pneumonia can also infect birds and other animals.
• Medical conditions | Some medical conditions such as heart disease or immunosuppression or lung diseases such as asthma and COPD.
• Hospitalisation | People who are in ICU, sedated or on a ventilator are at higher risk.

Symptoms can range from mild to serious and generally include a cough with or without phlegm. Other symptoms include shortness of breath, chest pain on breathing or coughing, fever, chills, fatigue, nausea and/or vomiting, and diarrhea.

Older people and those who have a weakened immune system may have fewer and milder symptoms, eg they may have a lower-than-normal temperature instead of a fever.

Newborns and infants may not show signs of infection, or display a range of unclear symptoms, eg; no energy and restlessness or vomiting, fever and cough, bluish tone to the skin and lips, grunting, pulling inward of the muscles between the ribs when breathing, rapid breathing and widening of the nostrils with each breath.

Hudson Institute researchers are focusing on overcoming and treating the severe consequences of pneumonia including

1. Inflammation – severe infections result in an overreaction of the immune system resulting in life-threatening damage to the lung. There are currently no effective drugs which treat the inflammation. This includes the acute inflammatory pneumonia caused by viruses such as SARS-COV-2.
2. Antibiotic/Drug resistance – bacteria can be resistant to antibiotics making some infections untreatable.

Current treatments depend on the type of pneumonia. Even people with a treatable bacterial pneumonia can suffer serious ongoing lung damage.

There are currently no effective treatments for viral pneumonia and in severe cases people may need to go to the hospital to receive oxygen therapy or ventilation. Recovery may take a week to a month, sometimes more.

How Serious is Pneumonia?

In 2019, 4,124 Australians died from pneumonia and influenza, and it was the ninth leading cause of death. In addition, each year there are about 77,500 pneumonia hospitalisations.

Globally, lung infections are the number one cause of transmissible death worldwide. Pneumonia killed more than 808,000 children under the age of seven in 2017, accounting for 15 per cent of all deaths in children under five.

Preventing pneumonia

Vaccines can help prevent some types of pneumonia such as pneumococcal pneumonia, influenza and COVID-19. Vaccines are free under the National Immunisation Program for at risk groups. God hygiene also helps to prevent pneumonia.