I find this particularly amusing since I'm just a few years older than you, and my father was among the first health officers to authorize mass immunizations against polio. Polio is mostly spread by people who don't wash their hands after using the toilet or changing a diaper. I'm sure you will be amused to know that when the oral vaccine came out it was in short supply, but whole families could be immunized by giving one dose to an infant, because the vaccine was contagious in the same way as the disease.
Your recollection of the science of the day is a false memory.
You all become authorities on everything. First, no museum guide would ever say....now you are saying that you know what every scientist and doctor in the country was saying about polio. And no....my recollection is not a false memory. We DID have to stay indoors and not go out. There was a fear in the country of this very thing. So please, don't assume that you can talk for all--I don't care how old you are.
Oh, and my kids say that I am older than dirt...how old does that make you? :)
It is possible that PC's mom heard "dirt" and later her memory translated it to "ground." My first wife came from a backwoods bayou family, and they were always doing things like this.