[Tax-chick]

They're called "tarabagan" out in the eastern steppes, and are generally believed to be the original source of the Y. Pestis pathogen. The fleas which actually spread the disease lived on a variety of (usually) rodent hosts.

In the American Southwest, bubonic plague is spread by fleas carried by native small rodents.

[IronJack]

Yep, mostly prairie dogs.

[SunkenCiv]

And voles, I’d guess, although a lot of people think I’m saying moles when I say voles, then when I explain, they reach for their smart phones because they th ink I’m making it up. The nerve. ;’)

Hanta virus is definitely hosted by smaller N American rodents.

http://pediatriceducation.org/2011/02/07/what-diseases-are-spread-directly-by-rodents/