Having had Norwalk virus, a.k.a. norovirus, a.k.a. winter vomiting virus several years ago, anyone who really has it has my utmost sympathy. It is *horrible*
Literally within seconds of feeling ill, you end up being sick out of both ends at the same time and you feel like you want to die, never mind feeoing like you're going to die. Temperature goes through the roof, then you feel freezing cold, then you throw up at the same time as it'c coming out the other end... Goes on for 48 hours and keeps you feeling weak for a week.
Ah yes, fond memories of that week in Leeds. Not!