I saw a man getting out of a car in London earlier today. It was black and shiny and he looked prosperous. But both his legs were withered and he had to use crutches to walk. I'm pretty sure he had been infected with polio as a child.
The last outbreaks in the UK were in the 1960s, and polio has almost been eradicated from the world, but not quite. Here is a pretty impressive report of how to respond to a case.
A couple of points of interest:
1. although polio causes paralysis, its spread is faecal-oral, so the samples you need for lab testing are faeces.
2. this exercise cost £20m: probably well worth the money.
Xinjiang is an interesting place geographically and politically.