It depends on what you mean by confront someone. If it means the animal sitting or standing there holding its ground, then yes. That's not behavior indicative of a sick or aggressive animal. Just one that is curious or used to being near people. If it means an animal that is snarling, walking in circles or showing other signs of impaired coordination, or in the process of rapidly approaching a person, then no. If an animal seems sick the best course is to back slowly away from the animal, keeping your eyes on the animal but not making eye contact.