Coronavirus vaccine trial participants report day-long exhaustion, fever and headaches — but say it's worth it

High fever, body aches, headaches and exhaustion are some of the symptoms participants in Moderna and Pfizer’s coronavirus vaccine trials say they felt after receiving the shots. While the symptoms were uncomfortable, and at times intense, they often went away after a day, sometimes less. The phase three trials are a critical last step needed to get the vaccines cleared for distribution.