Which parasite is commonly found in raw or lightly cooked seafood?

Anisakiasis is the correct answer because it refers to a parasitic infection caused by eating raw or undercooked seafood that contains larvae of the Anisakis simplex worm. This parasite is commonly found in various species of fish and squid, leading to gastrointestinal symptoms in humans after ingestion.

In the context of food safety, understanding the risks associated with consuming raw or lightly cooked seafood is essential, as this can lead to infection. Susceptible seafood items include sushi, sashimi, and ceviche, where fish may not be adequately cooked to kill the parasites.

The other pathogens listed do not correctly match the description of being commonly found in raw or lightly cooked seafood. For instance, Staphylococcus aureus is a bacteria that can cause foodborne illness but is more often associated with improperly stored foods, not specifically seafood. Norwalk virus (now known as norovirus) is primarily associated with contaminated food and water, including shellfish, but not directly with raw fish. Trichina spiralis is a roundworm commonly linked to undercooked pork rather than seafood. Understanding the specific connections between food types and associated pathogens is crucial for food safety practices.