Literally..
As the population of the planet gets ready to top 7 billion by Halloween, and maybe 10 billion some time in the near future, the feces will hit the fan. The problem of human waste is already an issue of health and safety, but the prospect of more passed movements on the planet earth comes with an additional weighty conundrum. What to do with all the excrement?
Toilets and even outhouses aren't everywhere. Doing business in a bush is still a popular way to leave out waste. In the end, hygiene education will be the key to survival. It's either learning to move the right way or moving away from the movements.
That or just hope flies work in overdrive.