Polio and post-polio syndrome  

Polio, also known as poliomyelitis, is caused by a highly infectious virus. For most people, polio is a mild illness and causes flu-like symptoms. However, polio can be potentially fatal. A severe case of polio attacks the nerve cells that help the muscles to function and can cause severe muscle paralysis (paralytic polio).

How common is polio?

In the past, polio was very common. It was a frequent cause of death and paralysis all over the world, particularly in young children. In England, there was a widespread outbreak of polio cases during the 1940s and early 1950s.

Due to the introduction of a polio vaccine in 1955, the number of polio cases has been dramatically reduced.

Since 1998, there have not been any reported cases of polio in the UK. There are now only four countries in which the condition remains a serious problem. These are:

• Nigeria
• India
• Afghanistan, and
• Pakistan

There is no cure for polio so it is important to prevent it from occurring. Make sure your child receives all their necessary immunisations. For more information, see the Health A-Z topic on childhood immunisation.

Post-polio syndrome

While polio is essentially a disease of the past, an increasing number of people are developing a poorly understood condition called post-polio syndrome (PPS).

PPS affects approximately 20-66% of people who have had polio. You may develop PPS between 10 and 40 years after your initial illness, with symptoms taking an average of 30 years to develop.

The initial symptoms of PPS include:

• increasing weakness
• stamina problems
• fatigue
• pain

You may have difficulty getting around or carrying out everyday tasks and activities.

The exact cause of PPS is unknown. One theory suggests that PPS is the result of the gradual deterioration of nerve cells in the spinal cord that were damaged by the polio virus. This would also explain why PPS can take years to appear.

The theory that the polio virus may lay dormant (inactive) in your system after the original infection has been disproven. Only people who have had polio can develop PPS and it is not contagious.

In recent years, PPS has become more common in the UK, largely due to the high number of polio cases during the 1940s and 1950s. However, as polio is no longer naturally active in England, PPS should become much rarer in the future.

There is currently no cure for PPS, although a range of treatments can help you to manage the symptoms. For more information, see Post-polio syndrome - treatment