Context

Africa has been declared free from wild polio by the independent body, the Africa Regional Certification Commission.

What is polio?

• Polio is a virus which spreads from person to person, usually through contaminated water. It can lead to paralysis by attacking the nervous system.
• Polio usually affects children under five, sometimes leading to irreversible paralysis. Death can occur when breathing muscles are affected.
• The disease is now only found in Afghanistan and Pakistan.
• There is no cure but the polio vaccine protects children for life.
• Two out of three strains of wild polio virus have been eradicated worldwide.

Types of Poliovirus

• There are three wild types of poliovirus (WPV) – type 1, type 2, and type 3. People need to be protected against all three types of the virus in order to prevent polio disease and the polio vaccination is the best protection. 
• Type 2 wild poliovirus was declared eradicated in September 2015, with the last virus detected in India in 1999.
• Type 3 wild poliovirus was declared eradicated in October 2019. It was last detected in November 2012.
• Only type 1 wild poliovirus remains. There are two vaccines used to protect against polio disease, oral polio vaccine and inactivated poliovirus vaccine.

How serious is polio?

• Polio, or poliomyelitis, mainly affects children aged under five.
• Initial symptoms include fever, fatigue, headache, vomiting, stiffness of the neck and pains in the limbs.
• It also invades the nervous system and can cause total paralysis in a matter of hours.
• One in 200 infections leads to irreversible paralysis. Among those paralysed, 5% to 10% of people die when their breathing muscles become immobilised.
• Polio can be easily imported into a country that is polio free and from there it can spread rapidly among under-immunised populations.
• The WHO says that it is important countries remain vigilant and avoid complacency until there is global eradication.
• For all types of polio to be eliminated, including vaccine-derived polio, vaccination efforts will need to continue alongside surveillance, to protect children from being paralysed by the disease in the future.