I was wearing an N95 respirator, but once I got into it I was seriously wishing I had put on a Tyvek suit. After several rounds of sweeping and cleaning and scooping and vacuuming, with an exhaust fan blowing dust out through the window, I took my clothes off in the laundry room and went straight to the shower.

Now Michael is in there bleach mopping the whole room. We're gonna let it dry out before going back in and doing more work.

Rat shit around here may contain Hantavirus and Leptospira bacteria.

The nests are also home to "kissing bugs" (family Triatominae) that spread Chagas Disease. The kissing bugs feed on your blood and poop on your skin. When you itch the bites, possibly unconsciously in your sleep, you can spread the feces into the wound, providing an entryway for the parasite Trypanosoma cruzi that causes Chagas disease.

I knew this was gonna be a big, gross job, which is why I had put it off for so long. But doing a search for what illnesses pack rats in Southern Arizona might carry, plus the increasing smell, was enough to convince me that It Is Time.

And just for fun they were cockroaches living under there too.

By the way, here's a pro tip for sealing up plumbing intrusions and making them rat proof and cockroach proof:

Wrap the hole with multiple layers of quarter inch or half inch hardware cloth nailed or stapled to the surrounding wood and wired tightly to the pipe. Create a multi layer wire cage in the opening. Then fill the whole space with spray foam.

Rodents will not be able to chew through this, it will keep out roaches and you get the added benefit of sealing against airflow.

This is what we will do around the drain pipe when we replace the bathtub. I'll post photos when we get around to it. But this method is cheap, easy and very effective.

Progress!
This is the bathtub area after all the rat poo had been cleaned up. I shoveled and swept it all out, then he used a shop vac on it, then we bleach mopped the whole room.

That flooring is 7/8" clear, old growth fir tongue and groove. It provides both the subfloor and the floor for the entire house. Subsequent remodels have involved putting 3/16 plywood over it, then carpet or stick-on cheap linoleum tiles on that, but I'm ripping that out and replacing it with probably 5/8 plywood. Only the bathroom is getting done right now.

Still haven't decided on the finish floor.

What the shower alcove looks like this evening at quitting time. I opened up the floor, removed the crappy old siding and scraped up all the old linoleum tiles.

The green you see is a tarp laying on the ground in the crawlspace underneath the house. I crawled under and spread it out to catch all the rat poo and cactus thorns that I knew would fall down there. I'll pull it out tomorrow and we'll get underneath there and start figuring out the new plumbing.