Thank. However, you need to understand that polio vaccines come in two cohorts: 1) The "modern" vaccines These vaccines require refrigeration and infrastruct

Thank. However, you need to understand that polio vaccines come in two cohorts: 1) The "modern" vaccines These vaccines require refrigeration and infrastructure to support. These are the type of vaccine we use in first-world countries. They immunize without the ability to mutate into a real polio virus. 2) The attenuated live virus vaccines These vaccines don't require refrigeration and consequently are the ones used in third-world areas with poor infrastructure. The problem is that occasionally it mutates into a fully functional polio virus. We don't use it in the first world, and we only use these in the third world when there is an active outbreak. The problem is that polio is now sufficiently suppressed that giving the attenuated virus vaccines cause more problems than they solve. Consequently, getting the last few pockets of polio stamped out is becoming really hard. You can't do a general immunization with attenuated virus as it will cause more cases than it prevents, and you can't get your refrigerated vaccines into the really backwards areas. I suspect this case in New York is fallout from the fact that England seems to currently have circulating polio that they haven't yet pinned down, though. We need the CDC to go make a trip to England and get that stomped out post haste.