On the first day of my vacation last week, I had just finished covering myself in sunscreen when I felt my knees go weak. I ran for the bathroom, where my body cleared itself of its contents with the fury of a surface-to-air missile. Almost as suddenly, my back and legs started feeling like they had been pounded with meat mallets. I crawled into bed, and there I stayed for the next 24 hours. If I had, at that point, possessed enough strength to shake my fist at the heavens, I would have done so and said, “Damn you, norovirus!”

Source: The stomach-flu mystery