Gene Hackman, who suffered from Alzheimer’s, lived in the house with his dead wife for a week before he died.
Of the three dogs living in the house, one died because it was locked in a carrier and therefore probably starved to death. The two free-living dogs were the only ones to survive.
Just a tiny bit of infected rat shit.
Actually the most common way is through aerosolized particles, meaning there is a ton of rat shit and piss somewhere in your living space (like an attic or crawlspace) and it gets into your air supply. Far less commonly but still possibly it can be through direct exposure to feces and urine, or even more rarely through a scratch/bite
Despite this it’s astoundingly rare. 20-50 cases annually for the entirety of the USA and less than 1000 from 1993-2022