Here's a rundown of incubation periods that I could locate from various sources on the internet:
Mustard Gas - No antidote - must deontaminate
Tabun,Soman,Sarin,VX - Minutes
Smallpox - 10 - 12 Days
Anthrax - 1 - 5 Days
Botulism - 12 - 72 hours
Plague - 1 - 3 Days
Marburg - Ebola - 2 -21 Days
Cholera - 12 hours - 6 Days
Tularemia - 1 - 10 Days
Q-Fever - 12 - 26 Days
Venezuelan Equine Encephalomyelitis - 1- 6 Days
Viral Hemorrhagic Fevers (VHFs - 7 - 14 Days
The scary part is that with some of these bio-agents, we could be fatally ill and not know it because the symptoms mimic common respiratory illnesses.