Hi, my adult children (age 22-30) are sick. Symptoms begin with severe leg pain, so bad they cannot stand up. Followed around 6 hours later with dizziness, vomiting, severe stomach cramps, diarrhea and back pain. They live in seperate locations but spend a good deal of time together. I have been away on business, so I'm not sick. Any idea on what this is? I am a nurse and was shocked about the severe leg pain for 6 hrs before other symptoms. Could it be haunta virus?