As someone who has had norovirus a few times, I've been able to recognize the tell-tale warning signs that something explosive is about to come. First, I usually have a sense that my stomach is not emptying fully. This is the result of the virus' action to ensure it has enough projectiles to hitch itself onto to make its way to another host. Next, hyper-salivation. Then, the run to the bathroom to vomit violently--this often just starts like a flick of the switch. Chills and muscle aches and pains usually follow.
Today, I was ready (or so I thought). As soon as I felt that delayed emptying sensation, I took an anti-emetic medication. However, it was too little too late. Though, it has kept the vomiting at bay for now.
Norovirus is so successful because of its contagiousness--when someone vomits they are a super spreader whose vomitus remains infectious. Additionally, the virus is resistant to standard cleaning agents (e.g. alcohol), making clean up challenging.
I wish there was a vaccine.