Polio (poliomyelitis) is a very serious, highly infectious disease, which is fortunately very rare in the UK because of immunisation against it (children in the UK have been immunised against polio since 1958).
The virus initially affects the gut before spreading to affect the nervous system and can cause muscle wasting, permanent paralysis or even death.
The polio virus is transmitted through contaminated food, drinking water and swimming pool water and faeces.
What are the symptoms of polio?
In 9 out of 10 cases, polio fortunately causes no symptoms and leaves no long-term effects.
In 5 per cent of cases there is flu-like illness that lasts two to three days and causes no other problems – this is sometimes called 'abortive polio' where the symptoms develop three days to three weeks after infection.
In about 1 per cent of cases, the signs of abortive polio are present but the headache, nausea and vomiting are much worse.
There may also be stiffness of the neck, trunk and limb muscles but this leaves no permanent damage, known as 'non-paralytic polio'.
However – and this is why polio can be such a feared illness – in about 0.1 per cent of cases paralysis occurs.
This type of paralytic polio can be very variable but usually just affects one limb and may affect breathing, eating, bladder and bowel function.
In some cases this paralysis gradually improves over many months, but some people are left with a permanent disability.
The greater the disease severity, the greater the risk of death.
Who is most at risk?
People who have not been immunised are at risk. Fortunately, most of the world is now polio-free following successful immunisation programmes.
In the UK, routine immunisation is offered to babies as part of the combined DTaP/IPV(polio)/Hib injection that protects against diphtheria, tetanus, pertussis (whooping cough), polio and Haemophilus influenza type b.
Booster doses are given to children before they start school and after they leave. Vaccination is the only way of preventing polio outbreaks.
What is the treatment for polio?
There is no specific treatment for polio so the best treatment, in effect, is to prevent it developing in the first place by immunising against it.
If it is a mild attack, then symptomatic treatment such as painkillers are all that are required.
If severe, then hospital admission is often needed, especially if breathing is affected.
Physiotherapy can be very helpful in regaining function in an affected limb.
What if I am travelling to an area of the world where polio is still present?
Pakistan, India and Nigeria are areas where polio outbreaks can still occur.
If you have had your normal childhood immunisations then you will be protected and not require a booster.
If you have not had a booster in the last 10 years and are travelling to a high-risk area then you may be advised to have one.
Your GP or practice nurse can advise you about this.
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