You'll suffer for 48 hours
At this point, you'll begin to feel very unwell, as your body's immune system twigs that something isn't quite right and begins to produce antibodies to fight the infected cells.
You may experience sudden projectile vomiting and watery diarrhoea as your body attempts to fight the infection. While this may be alarming in its unpleasantness, these are your body's natural trigger-responses, as your immune system toils to flush the particles out of your body. (The irony is, though, the worst side-effects of norovirus that keep us glued to the toilet are, in fact, completely pointless, as the virus affects the small intes- runs, Dr Henderson notes that you may experience stomach cramps, abdominal pain, fatigue and a mild fever while you're contagious.
The good news is, norovirus tends to leave as quickly as it arrives, usually lasting one to two days. People generally find they continue to feel weak for a few days afterwards, as the immune systems works overtime to battle against the infection, gradually locating the infected cells and deactivating them.