It is a shame that some fought so hard to make a comeback from the original attack, only to be struck down anew in later yrs.
I expect polio, along with cholera, diphtheria, typhoid, whooping cough and the other "childhood" diseases will come back in force when the sanitation breaks down in our cities. Clean water for drinking and bathing is imperative to combat these diseases. Diarrheal diseases continue to be a serious problem even with our modern sanitation. I once worked in a pediatric hospital. Part of the time I worked in the isolation unit. I got to where I could diagnose the particular bacteria causing a child to be ill, just by smelling the air in the room with that child. the doctors had to do a culture and sensitivity before they knew what was wrong. The nurses would know right away. The nurses also had to get nosy and find out what the reason was that the child contracted the disease so we could teach the mothers how to care for them. Invariably it was poor sanitation, though some diseases are so very contagious that you don't need a serious lapse in sanitation, some are pretty hard to catch. We saw a lot of the hard to catch ones in MS. Some mothers would fill a bottle for a baby from any source available, even an open pond or creek. Some admitted that the dog would lick the baby bottle and then the baby would suck from it. All sorts of dirty habits.
Once the hooey hits, breast feeding will become even more important as a means to prevent water born illness in infants. Everyone should also have a really good filter system. One that removes viruses is best, I have one of those, but boiling water that has been filtered thru cloth or sand will also work. Can't emphasize hand washing enough!