Polio

The War on Polio Just
Entered Its Most
Dangerous Phase

Though victory is close, the eradication campaign
is on some very fragile ground. 

This time two years ago, it must have felt as though the long international campaign to eradicate polio—launched in 1988 and decades past its hoped-for end date—was at last nearing its goal. There were only 17 cases of naturally occurring polio in the world in 2017, half the number from the year before and incomprehensibly fewer than the 350,000 cases that occurred annually when the campaign began.

The picture looks different now. The count for 2019 won’t be concluded until next year, but so far this year there have been 117 cases of naturally occurring polio. And in a galling development, there have been an additional 216 cases of what is called “vaccine-derived polio”—an accidental byproduct of the eradication campaign, brought into being by the campaign’s own vaccines.