How would our lives be different if we had never realized the existence of microorganisms. provide one example to support your awnser

Our lives would have be different if we never realized the Existence of microorganisms , as we would have wasted unhealthy we would never take bath property , we never kept our surrounding clean which may produce several diseases which could make us make us ill. We would have never been able to make vaccine for treatment like diseases like polio and many others.
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