A 77-year-old man presented to the emergency department with five days of episodic fevers, rigors, and night sweats. He described malaise and low appetite. There was no weight loss, headache, neck stiffness, cough, difficulty breathing, abdominal discomfort, joint pain, or rash. He returned three weeks ago from his annual trip to the Cape Cod region of the Northeastern United States. While there, he visited the beach and worked in his garden. He recalled no insect bites.