I have experienced a close bond with a dog in the past, I really refuse to let my emetophobia take that away from me the next time I have one. I really hope it's unlikely. Viruses can sometimes be species jumpers, but I'm not really sure that this constitutes proof that dogs are efficient vectors of norovirus. It's worth noting that many times a virus (like some forms of bird and swine flu) can jump from humans to animals or vice versa, but what makes them a big problem is when they can efficiently spread from individual to individual. It would be much more worrying if it were proven that dogs can easily spread human noro amongst themselves.