This is just wrong on so many levels:
1) The exposed population is being used in a clinical trial without their consent.
2) Once released there is no way to control what happens ... Murphy's Law and the law of
un-intended consequences suggests that the result may well be undesirable.
3) Cholera does not need a vaccine ... areas and populations that are vulnerable need the
infra-structure and development that eliminate the risk of cholera ... plumbing, clean water
systems, etc; Even if a natural disaster occurs that increases risk of cholera there is no
need for a vaccine, as clean water can be imported until the infra-structure is repaired.