Everyone reacts different to the stomach virus. I remember twice in my life, having it drawn out. Thirteen years ago when my kids were young, they all had the sv. vomiting, diarrhea, fevers, etc. Two days later I caught it-- I felt off and nothing sounded good at all to eat. It made me feel worse just smelling and thinking of food. I started getting waves of nausea for literally a whole day and a half. My major symptoms didn't start until night-time. I had extreme diarrhea and vomited twice. I had body aches, etc., for another whole day, once the vomiting/diarrhea stopped. I know for a fact I had the sv because I caught it from my kids who got it at school. Everyone' body fights off viruses differently. Think of it this way-- a person with a strong/healthy immune system may get the bug and fight it quicker than some people with weakened immune systems. My immunity sucked when my body tried fighting that virus. A lot of people fight the virus within 24 to 48 hours but some just can't.