A guest becomes ill after eating raw oysters and reports jaundice weeks later. Which of the Big 6 pathogens is a virus most associated with contaminated shellfish and infected food handlers?

解析

Hepatitis A is the only virus among the four, and it is the Big 6 virus linked to raw or undercooked shellfish and to infected food handlers with poor handwashing; jaundice appearing weeks later fits its long incubation. Shigella, Salmonella Typhimurium (a nontyphoidal Salmonella) and STEC strains such as E. coli O157:H7 are Big 6 pathogens too, but all three are bacteria — the deciding word in the stem is 'virus'.