In an area where there are high enough levels of immunity in the population, this usually does not present a problem...
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So if you are already immune to polio, you won’t be adversely affected by this vaccine which uses a live attenuated polio virus. In which case, you likely didn’t need the vaccine in the first place. Conversely, if you have no polio antibodies, this vaccine will give you polio. Sounds like a problem.
Third world Africa hellholes have always been an ongoing battle against diseases the rest of the world has put behind.