Bleach is a gift from the gods...
Actually bleach WILL kill almost all parasites. The problem that most people have is 1) the cage is not cleaned thoroughly of debris before bleaching, 2) they are not using a high enough concentration, and 3) they are not allowing proper contact time for the bleach to work.
When you have animals that are using the cage and you need to do maintenance cleaning a 10% bleach solution on the cage for about 10 to 15 minutes before rinsing is fine. (Remember that if you can smell the bleach after the rinse, you need to keep rinsing until it is gone.)
If you have an enclosure that has been exposed to an infectious agent or parasite you will have to take more care or throw the enclosure away.
Bleach only works by contact. Example- if you have a ball of feces with an oocyte in it and you dose the ball in bleach, if the bleach doesn't make it to the center, the oocyte is not harmed. So, if the cage is not completely cleared of fecal/organic material, it doesn't matter how much you clean, organisms can exist. Wood (untreated) will protect organisms. Hard to reach cracks and crevices will harbor organism.
It take time for the bleach to penetrate. If you just spray on the bleach and then immediately wipe it off, you are wasting your time. 10-30 minutes is really necessary for a good effective treatment.
If you have time and your material can handle it, a higher concentration of bleach 20-30% will help eliminate pathogens and parasites. Again, just make sure you rinse and rinse and rinse and rinse....to get rid of the smell before reusing the apperatus.
That's all I got.