Key points about pneumonia

  • Pneumonia is an infection of your lungs. It's usually caused by bacteria or a virus, and is often triggered by a cold or the flu.
  • Young children and older adults are often worst affected and may need to stay in hospital for treatment.
  • Mostly it can be treated at home with rest, plenty of fluids and antibiotics but see your doctor if you have a chest infection that's not improving.
  • Get immediate help if your child develops a chest infection after a cold or the flu, or you have severe symptoms (eg, rapid breathing or difficulty breathing, chest pain, confusion, persistent fever or if a bluish tinge develops in your skin, lips and nail beds).
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Pneumonia is an infection that causes inflammation of the air sacs in one or both lungs. It happens when your body’s immune system is overwhelmed, such as during a cold or a bout of the flu, and can’t fight off the bug causing the infection. When infection sets in, the air sacs in one or both lungs fill with pus and fluids, making breathing difficult.

Video: How pneumonia affects the lungs

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(BupaHealth, NZ, 2013)

Pneumonia is usually caused by a bacterial or viral infection, but it can be difficult to tell which is causing a particular case of pneumonia.

Pneumonia in adults is usually the result of a pneumococcal infection, caused by bacteria called Streptococcus pneumoniae. Many other types of bacteria, including Haemophilus influenzae and Staphylococcus aureus, can also cause pneumonia. 

Viruses, such as respiratory syncytial virus (RSV) and the flu virus, are common causes of pneumonia in children.

Pneumonia can also be caused by fungal infections but this is fairly uncommon.

Anyone can develop pneumonia, but the risk is greater in babies and children aged 4 years and under and adults older than 65 years. Other risk factors include:

  • recently having had a cold or the flu
  • having a chronic lung condition
  • having a weakened immune system
  • smoking
  • drinking excessive alcohol 
  • being a patient in hospital.

In children, the risk of pneumonia is increased by:

  • premature birth
  • poor nutrition
  • low birth weight
  • not being breastfed
  • exposure to tobacco smoke
  • lack of insulation and heating at home
  • living in damp, mouldy and/or overcrowded conditions.

The symptoms of pneumonia can develop suddenly over 24–48 hours or they may come on more slowly over several days.

Common symptoms of pneumonia
  • cough (often with yellow or green coloured phlegm)
  • fever, which may be mild or high
  • shaking chills
  • shortness of breath
  • increased effort required to take a breath
  • low energy and fatigue
  • loss of appetite
  • headache
  • chest pain that gets worse when you breathe deeply or cough.

See your doctor if you have a chest infection that is not getting better.

Get help straight away if:

  • your child develops a chest infection after a cold or the flu – children can become very sick very quickly if they develop pneumonia
  • you are experiencing severe symptoms, such as rapid breathing or difficulty breathing, chest pain or confusion, persistent fever or if a bluish tinge develops in your skin, lips and nail beds.

To diagnose pneumonia your doctor will take a medical history and do a physical exam. Pneumonia may be suspected if they hear coarse breathing, wheezing or crackling sounds when listening to your chest through a stethoscope.

A chest x-ray is not usually necessary but may be used to help diagnosis in some cases.

Mild cases of pneumonia can be treated at home with rest, antibiotics and drinking plenty of fluids. However, pneumonia can be severe and require hospital admission or intensive care unit (ICU) admission. It can lead to death particularly in those who are older or with other health problems.

Hospital admission is often recommended for babies, young children and older adults and for those with severe disease. It is important to take your treatment and see a doctor if you or child is not improving or you or your child develop severe symptoms. 

Antibiotics can be used to treat pneumonia caused by bacteria but are not effective if it is caused by a virus. However, it is difficult to tell if pneumonia is caused by bacteria or a virus, so antibiotics are usually prescribed if pneumonia is diagnosed.

Treatment at home

If your treatment is at home, you need to take all the antibiotics prescribed and see your doctor for review as recommended. If your symptoms do not improve or get worse after you have started treatment, tell your doctor. 

If possible, have someone stay with you or check in on you while you are unwell. Make sure you have access to a phone and are able to contact your doctor or emergency services if required.

To help your recovery:

  • take antibiotics as prescribed
  • drink plenty of fluids, mainly water
  • avoid smoking or passive smoking 
  • take medications (such as paracetamol or ibuprofen) if required for relief of pain and fever.

Treatment in hospital

If you need treatment in hospital you'll be given antibiotics and fluids intravenously through a drip, and you may need oxygen to help your breathing.

Once you have started treatment, your symptoms should improve steadily. However it may take a few weeks to months to recover fully. How quickly you improve will depend on how severe your pneumonia is. 

To help prevent pneumonia, do the following:

  • Get the flu vaccination every year – it can help prevent pneumonia caused by the flu virus. Read more about the flu vaccine.
  • Get a pneumococcal vaccination – this vaccine is especially recommended for anyone at high risk of pneumococcal pneumonia. Read more about pneumococcal vaccine.
  • Stop smoking – smoking damages your lung's ability to fight infection. Read more about tips to quit smoking.
  • Wash your hands often or use an alcohol-based hand sanitiser.
  • Stay rested and fit.
  • Stay home when you're sick.
  • Avoid people who have a cold or the flu.

Pneumonia vaccination

In New Zealand there are 3 different brands of pneumococcal vaccine – Pneumovax 23®, Prevenar ® and Synflorix®.

  • Most infants should receive the pneumococcal vaccine (Synflorix) as part of the New Zealand Immunisation Schedule(external link) at 6 weeks, 5 months and 15 months of age. They are not fully protected until they’ve had all the doses.
  • Infants on a high-risk pneumococcal schedule may receive their doses of the pneumococcal vaccine (Prevenar 13) at 6 weeks, 3 months, 5 months and 15 months of age.
  • Some older children and adults with weakened immune systems who are at risk of pneumococcal infection may be eligible for vaccination (Pneumovax 23). Check with your doctor or nurse about your eligibility. Read more about pneumococcal vaccine.

Pneumonia – an overview(external link) NHS, UK
Pneumonia(external link) KidsHealth, Paediatric Society and Starship Foundation, NZ
Childhood pneumonia(external link) Asthma and Respiratory Foundation, NZ


  1. The management of community acquired pneumonia(external link) BPAC, NZ, 2012

Childhood pneumonia statistics

A report on the impact of respiratory disease in New Zealand (2018), found significant differences in childhood pneumonia rates were for Pacific peoples, and for those in the most deprived quintile. Pacific children’s pneumonia rates were 2.4 times higher than the non-MPA rate for hospitalisation, and 5.6 times higher for mortality; Māori children’s rates were 1.6 and 4.1 times higher respectively. Hospitalisation rates for 21 Asian children were 1.1 times higher. These differences were greater in children aged under 5 years.

Childhood pneumonia rates were highest in the most deprived areas, with hospitalisation rates 2.1 times higher in the most deprived NZDep quintile than in the least deprived. Over half of deaths were in the most deprived quintile, making the NZDep9-10 mortality rate 8.1 times higher than that of NZDep1-2.

Source: The impact of respiratory disease in NZ – 2018 update(external link)

Guidelines and pathways

Navigating uncertainty – managing respiratory tract infections(external link) BPAC, NZ, 2019
Acute pneumonia in infants and children(external link)
 Starship Children's Health Clinical Guidelines, NZ, 2010
The management of community-acquired pneumonia(external link) BPAC, NZ, 2012
Te ha ora – the breath of life – National respiratory strategy(external link) Asthma & Respiratory Foundation, 2015, NZ
Pneumonia in adults – diagnosis and management(external link) NICE, UK, 2014
Primary care summary of guidelines for management of CAP in adults(external link) British Thoracic Society, UK, 2009

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Credits: Healthify editorial team. Healthify is brought to you by Health Navigator Charitable Trust.

Reviewed by: Dr Veronica Playle, Clinical microbiologist, Auckland

Last reviewed:

Page last updated: