If there is mouse poop on it, then they have most likely peed on the box, too. Ingesting rodent crap can kill you. It's not worth the price of pasta.
Can/would you get a cat? We live out in the country and we struggled with mice for over a year until we finally decided we had no choice but to get a cat. We have two cats now and the mouse problem has virtually disappeared.
DO NOT use mouse poison. We made that mistake. They go off and die somewhere and you go crazy trying to find it, and by the time you find it, the body is this disgusting decomposed mess that you literally have to SCRAPE off the floor. OK, sorry to be gross, but now you know what you're in for!
Use mousetraps. Bait them with peanut butter -- every mouse's favorite food. We've tried several different fancy kinds of mouse traps but the plain old-fashioned ones work the best. The only problem is having to steel yourself to pry up the trap and take the dead mouse out. Luckily in my house it's DH's job to empty the mousetraps.
You can also stuff holes with steel wool -- they won't chew through that. No guarantee they won't just chew a hole right next to the steel wool, though.
Unfortunately, once you get mice, it is really tough to get rid of them. But I wish you luck anyway. Count yourself lucky -- at least you don't have snakes as well, like we do.
-------------------- jen
"It's one of the most serious things that can possibly happen to one in a battle -- to get one's head cut off." -- LC