Polio in the world today

While polio cases have decreased by over 99% since 1988 and the Americas, Europe, South East Asia and the Western Pacific have been certified polio free (due to the global effort to eradicate the disease), the poliovirus can easily be imported into a polio-free country and can spread rapidly among unimmunised populations. Afghanistan, Nigeria and Pakistan are still polio-endemic countries (countries that have never interrupted the transmission of the wild poliovirus). Failure to eradicate polio from these last remaining strongholds could result in as many as 200 000 new cases every year, within 10 years, all over the world.

Attacks on vaccination campaigns, in Pakistan in particular, have allowed the virus to spread across borders. Syria, which was polio-free for 14 years, was re-infected with the virus from Pakistan and refugees are still pouring out of Syria to countries such as Jordan, Lebanon and Turkey. Checking whether all these people have been vaccinated is impossible.

What is polio?

Polio is a crippling and potentially fatal infectious disease caused by a virus. It invades the nervous system and can cause total paralysis in a matter of hours. Initial symptoms are fever, fatigue, headache, vomiting, stiffness in the neck and pain in the limbs. One in 200 infections leads to irreversible paralysis (usually in the legs). Among those paralysed, 5% to 10% die when their breathing muscles become immobilised.

Current statistics

In 2013, WHO recorded 417 cases of polio worldwide (65 in Somalia, eight in Kenya and 35 in Nigeria at mid-July alone). Sixty-eight cases were already recorded globally by 30 April 2014 (up from 24 during the same time in 2013). As at July 2015, eight new cases of polio were reported in Madagascar, 26 new cases were reported in Pakistan and four in Afghanistan.

Good news

While there is no cure for polio, a polio vaccine given multiple times can protect a child for life. Children should get four doses of IPV. The first at two months, the second at four months, the third between 6 and 18 months, and a booster dose between 4 to 6 years. Adults who have never been vaccinated against polio should get three doses of IPV: the first dose at any time, the second dose 1 to 2 months later, the third dose 6 to 12 months after the second. Adults who are at increased risk of exposure to the poliovirus and who have previously completed a routine series of polio vaccine can receive one lifetime booster dose.

Sources

www.bbc.com/news/world
www.cdc.gov/polio/progress
www.polioeradication.org
www.who.int/

(Revised by M Collins)