What is polio?Polio (also known as poliomyelitis) is a contagious, viral infection that can cause paralysis and death. Australia is now polio-free, but immunisation is still important to prevent cases of polio from recurring.
What are the symptoms of polio?
Most people who become infected with the polio virus don't become ill and are not aware that they have the infection.
A minority of people infected with the polio virus have flu-like symptoms, which can last for up to 10 days, including:
- nausea and vomiting
- sore throat
- pain or stiffness in the back, neck, arms or legs
- weak or tender muscles
About 1 in 50 people infected with the virus go on to develop severe muscle pain, with back or neck stiffness.
Fewer than 1 in every 100 people who become infected develop severe muscle weakness, known as acute flaccid paralysis, acute poliomyelitis or infantile paralysis. This can affect arm, leg, head and neck muscles, and the diaphragm, a chest muscle vital for breathing. Although most people recover completely, others develop irreversible paralysis, and some die.
How polio spreads
The polio virus is highly contagious. It spreads if someone has direct contact with people who are already infected. Less often, it spreads through food and water contaminated with the virus. In parts of the world with poor sanitation, this can occur through untreated sewage.
The virus can be in faeces for up to 35 days before the person infected shows any symptoms, and it can stay in their faeces for up to 6 more weeks once symptoms have appeared. Even so, around 19 out of every 20 infected people have no symptoms. This means the polio virus can infect thousands of people before it is noticed.
Who is at risk from polio?
In the parts of the world where polio still exists, it can strike at any age, although it mainly affects children under 5.
People who are not immune to the polio virus may become infected if they travel to areas with polio. They may also take the infection with them to polio-free countries, including Australia, and could potentially infect others.
If you plan to travel to an area where polio occurs, or care for people with polio, ask your doctor about precautions. Even if you have been vaccinated, you may need a booster dose to ensure you are immune.
Read the Recommendations for Australian Travellers from the Department of Health for more information.
Polio in Australia
Polio used to affect significant numbers of people and caused some deaths. Australia began mass vaccination against polio in 1956, and the country's last polio epidemic was in 1961-62. In 2000, Australia was officially declared polio-free.
Today, many people who have survived polio experience problems known as the 'late effects' of polio, or post-polio syndrome. Read more here about the late effects of polio.
If you have symptoms of polio, see a doctor immediately.
If your doctor suspects polio based on your symptoms, you will be asked if you've travelled to a country where people still have polio or contacted someone who has.
Your doctor will confirm a polio diagnosis by taking a sample from your throat, stool (poo) or cerebrospinal fluid (the fluid surrounding your brain and spinal cord).
Treatment aims to help people with polio recover and to prevent complications. Depending on the severity of the condition, treatment may include:
- medicines for pain relief or to reduce muscle spasm
- intensive care in hospital, including help with breathing
- physiotherapy to aid recovery from paralysis
Polio can only be prevented by immunisation. Australia's National Immunisation Program provides children with a series of free polio vaccinations, which are given by injection.
Adults who travel to countries with polio, or look after patients with polio, should have a booster every 10 years.
Read more here about the National Immunisation Program's polio immunisation service.
Last reviewed: December 2018