The implementation of regular garbage collection, sewage treatment, food inspection, and other steps to preserve public health happened partly as a result of the discovery of which are microorganisms that result in diseases.

Pathogens

Explanation:

A pathogen or infectious agent is a biological agent that causes a disease or illness to its host. A pathogen can usually affect the normal physiology of a multicellular animal or plant (although they can also affect unicellular organisms).

Pathogens can be found on unclean environments such as garbage, sewage, rotten food.

Thus, the implementation of regular garbage collection, sewage treatment, food inspection and other steps to preserve public health happened as a result of the discovery by scientifics of pathogens, microorganisms that result in diseases.  

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