||An outbreak of polio in Namibia, Africa, has prompted a fresh warning that the disease may be poised for a comeback.
The warning comes as the number of confirmed cases of polio in Namibia has hit 19, with a further 150 cases suspected, although until this recent outbreak the country had been free of the disease since 1995. Unusually, the outbreak has affected mainly adults, who get much sicker with polio than children do.
These adults probably missed childhood vaccination and had not developed a natural immunity by encountering wild forms of the virus. Levels of wild virus have plummeted since vaccination began in the country, leaving Namibians defenceless when the virus turned up from elsewhere - in this case from Angola, which in turn got it from Uttar Pradesh, India, where the disease remains endemic.
Bruce Aylward, head of the World Health Organization's polio eradication drive, said: "This just shows that we have to eradicate polio everywhere because, while endemic areas persist, the virus will find susceptible people”.
He added: "There are bigger immunisation gaps than at any time in the last 25 years.
"If the virus exists, it will blow up in an area”.