I have only just read this... Expat, I hope that everyone gets well, soon. I am passing on healing vibes, your way.
I don't blame you, adults should have more common sense than that! They would not be allowed to set foot in the same block, as far as I would be concerned, and I know that I would have to be the one to anforce it, but this is your baby's health. She does not have her immune system built up to fight that sort of crap off, yet.
If you see them in the near future, kick their asses!