I’m generally a calm and easy-going kind of person but this evening, I was overtaken by a state of extreme agitation after watching a music video. I experienced a mild feeling of irritability that eventually turned into full-on shivers down my spine, like a low that comes at the end of a liquid sugar rush. It is a scientific marvel, and may well be the first time that anyone has ever caught a disease directly through an iPhone. There is a name for it: Dengue Fever.