Well I thought v* was just happends more in children. I know you definetly get d*, but I don't think you always get v*. And I also think that some people have sensitive stomachs, and if they feel even a little nausous they v*. And some people don't care about v* at all so if they feel sick they v*. But I see your point, I don't know how you can't get d*...Unless those people are just too embarassed to say they had it??