Polio is a contagious virus that can be transmitted from person to person, but also through contact with contaminated food and water or faeces and objects that have been in contact with an infected person.
Often the virus goes unnoticed, but the virus can also cause flu-like symptoms, such as high temperature, fatigue, headache, vomiting, a stiff neck and muscle aches. These usually last about ten days, but can eventually lead to serious and even life-threatening symptoms, such as paralysis of the respiratory muscles.
The virus mainly affects young children, although it can also affect unvaccinated adults. Successful vaccination campaigns have eradicated the virus from most parts of the world, although it can still be found in countries such as Afghanistan, Nigeria and Pakistan.