Now only one of the three strains of polio remains
24 Oct 2019
BBC – The second of three forms of the poliovirus has been eradicated, experts have announced.
There are three types of the wild poliovirus, which, while scientifically different, cause the same symptoms, including paralysis or even death,
The world was declared free of type 2 four years ago – and now the World Health Organization has said type 3 has also been eradicated.
But type 1 is still circulating in Afghanistan and Pakistan.
Polio usually affects children under five. The WHO estimates one in 200 cases leads to irreversible paralysis. Death can occur when breathing muscles are affected by the paralysis.
There is no cure but the polio vaccine protects children for life.
Cases of wild polio have fallen by 99% since 1988.
The declaration type 2 had been wiped out was made in 2015, a full 16 years after the last case was seen in India.
It has been seven years since the last case of type 3 polio was detected, in northern Nigeria.
Since then, experts from the Global Commission for the Certification of Poliomyelitis Eradication, of which the WHO is a member, have watched patterns of polio cases to be sure type 3 had been eradicated … Read more.