“Your body thinks it’s cold, so you shiver and you have the repeated shaking that comes from shivering," Landon said. "So adding those is kind of redundant with fever. Muscle aches also could fall under the same umbrella. You generally just ache or feel sore or weak with a fever, and muscle pain also can be common because you really do use a lot of muscles to shiver, especially if shivering for an extended time.”