The word is that the Spanish and Americans have been sloppy - very sloppy.
Really interestingly, Nigeria has dealt brilliantly with it - not something you'd expect. But it's because Nigeria is the last place where polio exists and there's been an international effort to wipe it out there. As a result, they have the equipment, and more importantly, the procedures to deal with it and are very accustomed to the problems.
Life, don't talk to me about life - Marvin the Paranoid Android
"Science adjusts it's views based on what's observed.
Faith is the denial of observation so that Belief can be preserved."
- Tim Minchin, in his beat poem, Storm.