Which "Big Six" disease can be contracted from shellstock?

The correct answer is Hepatitis A, which can be contracted from shellstock, particularly when these shellfish are harvested from contaminated water. Hepatitis A is a virus that affects the liver and is commonly transmitted through the fecal-oral route. When shellfish, such as clams or oysters, filter water for feeding, they can accumulate pathogens like the Hepatitis A virus if the water is contaminated with fecal matter from infected individuals.

The reason Hepatitis A is associated with shellstock lies in the nature of how shellfish are harvested and prepared. If shellfish are harvested from contaminated waters and not properly cooked, the virus can survive and pose a health risk to individuals consuming them.

While Salmonella, Norovirus, and Listeriosis are all significant foodborne pathogens, they are typically associated with different sources. Salmonella is often linked to poultry, eggs, and sometimes seafood, while Norovirus is highly contagious and usually spread through contaminated food or water, as well as person-to-person contact. Listeriosis is primarily connected to ready-to-eat deli meats and unpasteurized dairy products. Thus, their connections to shellstock are less direct than that of Hepatitis A.