You are dispatched to a residence for a 61-year-old woman wi…

You are dispatched to a residence for a 61-year-old woman with flu-like symptoms. Upon your arrival, the patient greets you at the door. She complains of a headache and nausea, and tells you that she has vomited twice. Her husband, who is lying on the couch in the living room, began experiencing the same symptoms at about the same time. You should: