***They should kill all the cats in the city.***
The English killed off all the dogs and cats in 1665 to stop the Great Plague. They also lit bonfires to drive off the “bad air”.
It didn’t work. The plague began to wain, then the Great fire afterward cleansed the city of London.
That's where you get the fascinating medical term: "malaria" which literally means: bad air (mal = bad, aria = air).
Turns out, you get Mal-Aria from mosquitoes instead of bad air, unlike airborne diseases. ...but hey, mosquitoes do fly in the...air!