@WSpunkmeyer @greggwbarnes @benny171a @TrumpUndead @jonathanchait The main reason people don't get polio despite most in developed countries using a vax that does not stop infection is polio largely eliminated by a combination of public health measures and previously using a more effective vax. That may change with polio starting to spread now.

@WSpunkmeyer @greggwbarnes @benny171a @TrumpUndead @jonathanchait 尽管大多数发达国家使用不能阻止感染的vax，但人们没有感染脊髓灰质炎的主要原因是脊髓灰质炎在很大程度上是通过公共卫生措施和以前使用更有效的vax的组合来消除的.随着脊髓灰质炎现在开始传播，这种情况可能会改变。