As for handling hygene issues with regards to human waste post SHTF (pun intended, of course), I'm a big believer in a clivus multrum.
Basically, it's an underground chamber built on a slant (a 45° angle, if my memory serves), with a toilet seat over the top opening.
It's mostly odorless, it's hygenic (as it doesn't let waste into the environment), it doesn't use water, it has no moving parts to speak of, and it supplies fertilizer after about 4 years.
It doesn't even require plumbing.
They are often put on golf courses so that the owners don't have to spring for pipes, water supply, etc..