A Downside of Eating Out for this Middle-Aged Man

Potential for infection is everywhere for patients with alcoholic cirrhosis.

A 55-year-old man with alcoholic cirrhosis presents to the hospital with fever, chills, and malaise. He denies any ill contacts and was feeling well a few days ago. He reports eating at a seafood restaurant 2 days before his illness.

Which of the following organisms is the most likely cause of his symptoms?