The marathon to eradicate polio is on its final lap: the world is more than 99% of the way to success. After millennia of living with poliovirus and suffering the paralysis it causes, today nearly all the world’s people live in polio-free countries; two of the three strains of wild poliovirus (WPV) have been eradicated. Some 20 million people are walking who would have been paralysed had it not been for the efforts of national governments and health workers. If eradicating polio has been a marathon, the finishing line is in sight.