Wild-type and vaccine-borne variants of the disease still pose threats, US authorities say.

While substantial progress has been made in eradicating polio, efforts must now focus on preventing the devastating disease escaping hundreds of diagnostic and research laboratories across the planet, urges a new report from the Centres for Disease Control and Prevention (CDC) in Atlanta, US.

Of the three naturally occurring “wild type” polioviruses, type 1 has been reported only in Pakistan and Afghanistan since 2017, type 3 has not been reported since 2012 and type 2 was declared eradicated in 2015. With wild type 2 effectively banished, in 2016 the World Health Organisation (WHO) Global Polio Eradication Initiative recommended a worldwide withdrawal of vaccines containing the virus. There was, however, a hitch.

Read the full article in Cosmos magazine here