I don't purposefully disinfect my diapers. I may have used bleach twice (?) if something was particularly foul or to freshen up.
The thing is, the hot water in the hot water wash is not hot enough to kill anything. Most "bugs" (germs, etc) thrive at 98.6 degrees, which is why they like us.
Most people have their thermostat on the hot water heater set @ 120 degrees, which is good, because it helps prevent burns. But, it's def not hot enough to really kill anything in the wash. Only boiling water does that. I still wash my diapers in hot water. Either because of habit or I feel like the diapers get cleaner.
The dryer, however, will get hot enough to kill things. That's where my "incidental" disinfection comes in. Also, hanging dipes out in the sun will disinfect.
Bleach will certainly disinfect, but it's very wearing on fabrics, and I would not do it often (like I said, I've done it maybe 2 times in 6 months).
Many people may be sensitive to bleach, but diluted in the wash with 2 rinses should remove any residue. (Did you know that there is a wound rinse called Dakins solution made from bleach? I've used it on patients before. You pour it all over the wound, or make a packing soaked with Dakins. I was really surprised the first time I used it, but it really does help with certain types of wounds, like certain burns.)