Frequently Asked Questions

What is polio?    About Post Polio Syndrome     About polio vaccination

Motor neurons are nerve cells in the spinal cord, which control movement. They send messages from the brain and spinal cord via a long nerve fibre or "axon" that travels to a muscle and branches out into the muscle fibres. Each muscle can be controlled by many motor neurons.

This diagram shows an example of a motor neuron, which controls movement of the biceps muscle in the upper arm (Helen Chown). Click to enlarge

This can lead to muscle paralysis, affecting any part of the body, or death. Life saving measures may be needed in severe cases and many people remember the use of huge, body-enclosing respirators, known as "iron lungs" to help people with breathing problems - see picture.

Young children are more vulnerable but adults can also be affected by polio.

Polio is assumed to have been around for thousands of years. There is probable evidence from ancient Egyptian carvings from around 1500 BC, showing a man with what looks like the typical effects of polio. There is a widely accepted theory that in the past people became immune through exposure to a common mild flu-like illness in early childhood, with only a few becoming paralysed.

Epidemics, affecting larger numbers of people, only started to occur in the late 19th century. The largest epidemic in the UK was in 1950, affecting nearly 8,000 people but the last polio epidemics in the UK were in the late 1950s and early 1960s.

With the introduction of a comprehensive and continuing vaccination programme, there are currently no new cases of polio in the UK but it is estimated that there are as many as 120,000 people in the UK who survived polio. Although many were left with varying degrees of weakness, paralysis, fatigue, muscle pain, breathing and orthopaedic problems, others only had limited paralysis or appeared to have made a full recovery.

We now know that people who had polio may develop new symptoms years later. For some, these new symptoms are the result of the original polio-related weakness, orthopaedic problems or other illness, but in others they may be Post Polio Syndrome (PPS).

Travelling abroad
Before you travel to any of the countries considered a risk for polio, you should ensure that you are adequately vaccinated against polio and should seek specialist travel health advice. Your GP or practice nurse should be able to advise or you may wish to visit www.immunisation.org.uk or www.fitfortravel.scot.nhs.uk

Because there are three types of poliovirus, people who have had polio should also be vaccinated if travelling to "at risk" countries. It is thought that infection by one type of poliovirus is not thought to give immunity against potential future infection by one of the others

World situation
The World Health Organization estimates that there are 10 to 20 million people with polio worldwide. It is thought that up to 120,000 people in the UK had polio.

Since 1988 the Global Polio Eradication Initiative have organised for around 2 billion children around the world to be immunised against polio. Polio still exists, but the number of cases has decreased by 99% since 1988. In 2006 polio was endemic in just four countries: India, Nigeria, Pakistan and Afghanistan.

However, the poliovirus can easily be imported into a polio-free country and can spread rapidly amongst unimmunised populations. Between 2003-2005, 25 previously polio-free countries were re-infected due to importations.

The Global Polio Eradication Strategic Plan 2004-2008 outlines the key strategies to eradicate polio from the world. For further information: www.polioeradication.org

For further information see our leaflet "Polio Vaccination - what you need to know".