Since Cholera affects only humans, and also doesn't have an insect vector or animal reservoir host. And Polio is a disease of the central nervous system, spread from person to person through infected fecal matter entering the mouth. Then which one of them can be controlled by killing the vector, I'm not completely sure if cholera doesn't have a vector, but if they don't, then I'll like to know if and how polio can be controlled by killing the vector.
Both of these diseases do not have vectors, Cholera is a foodborne / waterborne disease and Poliomyelitis is spread through fecal-oral or oral-oral contact with an infected person. They both only infect humans.
Thus, both cannot be controlled through killing any vector.
The best way to prevent Cholera is to avoid potentially contaminated food and water and follow proper sanitation practices.
The best way to prevent polio is through immunisation via vaccines.
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