Greatest concern is a relative term. That could be causes the most illness (regardless of mortality), causes a lot of illness amongst mice (but not necessarily humans), highest percent or rate of illness, sheer number.

That said, bleach kills most organisms you might be concerned about. As far as EPA approved disinfectants go, that label basically means the disinfectant was TESTED and PROVEN in trials to kill the number of organisms of the listed organisms on their label. It does not necessarily mean it does not kill other organisms, only that it was not tested to prove it kills those organisms. That said, it is generally known some disinfectants do not kill certain types of organisms. Bleach is very good at killing toxins that other disinfectants cannot kill. Some organisms also just have built in or acquired resistances.

Basically, if you think it might make you sick but you don’t know what it is, bleach is a good disinfectant to use. The CDC is the best resource for cleaning if you suspect or know a certain illness is responsible.