It is spread by fleas that live on rats. If you have a rat problem, get rid of the rats. Problem solved. Unfortunately, rats are hard to get rid of, consider Nazi Pelousi and San Francisco.
Geebus, could Nanzi Pelosi and democrats be encouraging filth and vermin on their streets so as to grow rats in order to spread a plague?
I cannot believe I even thought of such a scenario as something with greater than a zero % possibility.
But why else would they allow people to CRAP IN THE STREETS???