Outbreaks of ______ traced to contaminated shellfish between 1900 and 1925 led to the PHS Certification of dealers involved in interstate shipment?

The outbreaks of typhoid fever traced to contaminated shellfish between 1900 and 1925 were significant in prompting public health measures, including the establishment of the Public Health Service (PHS) Certification for dealers involved in the interstate shipment of shellfish. Typhoid fever, caused by the bacterium Salmonella typhi, can be transmitted through contaminated food and water, including shellfish harvested from polluted waters. These outbreaks highlighted the critical need for regulations to ensure the safety of food products being transported across state lines, especially those that could carry pathogens responsible for such serious illnesses. The PHS Certification aimed to protect public health by ensuring that shellfish were sourced from safe and sanitary environments, thus significantly reducing the risk of foodborne illness associated with seafood consumption.