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In the 1700-1900s, common diseases included smallpox (virus), cholera (bacteria-contaminated water), tuberculosis (bacteria), influenza (virus), typhoid fever (bacteria-contaminated food/water), and malaria (parasite-mosquitoes). Poor sanitation and limited medical knowledge contributed to their spread and limited medical knowledge - best explain what are the caused of these diseases.
Added 7/20/2023 4:56:17 PM
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