Virus particles enter the body through the nose or mouth, travel to the stomach, but it’s only when they hit the small intestine that they start multiplying and irritating the gut lining — then the vomiting and watery diarrhoea strikes.
“This is the body saying, ‘Get it out, clear it, clear it, clear it!” says Dr Roger Henderson.
You might have stomach cramps and a headache too. The good news is it passes quickly and you should be fine in a few days, though some people do suffer worse than others. “That’s probably linked to the viral load you’re exposed to,” notes Henderson. “If you’re exposed to a very heavy viral load, you might feel worse.”
“There’s no cure for norovirus, it’s just a case of treating the symptoms,” Henderson stresses, which means a trip to your GP’s probably going to be futile — and put other people at risk. “It’s a miserable thing to get, but the vast majority of people will bounce back quite quickly. What they should not do, if they can, is walk into a doctor’s surgery —because we’re going to say, nicely, ‘Go away’ and give them general advice. But in the meantime, they’ll have sat there spreading their germs left, right and centre.”
Like flu, norovirus can be “more risky in the very young and very old”. While it’s highly unlikely to be a threat to the majority of people, with a vomiting and diarrhoea bug, the biggest risk is often linked to dehydration, which can quickly become serious - particularly for, as well as babies, young children and older people, those with pre-existing conditions like diabetes or a heart or kidney condition.
“The dangers [of dehydration include] reduced levels of consciousness, impact on your kidney function, altered confused states, and more prone to falls in the elderly,” says Henderson.”
“In terms of treatment, fluid replacement is the main thing,” says Henderson. “You can take paracetamol and ibuprofen for aches and pains if you want to, and avoid certain foods — spicy foods, oily foods —most people won’t want them anyway,” he adds. “Little and often” is often the best approach with eating. “Some toast, dry biscuits — everything is fine, to keep your sugar levels up, but the most important thing is fluids.” If you’re vomiting lots, Henderson notes that “if fluid stays down for at least five minutes, at least half of it will have gone into your system.
“Fluid replacement products and sachets like Dioralyte can be really helpful.”
There’s lots of pressure to ‘battle through’ and not take time off sick, but while you may feel fine once the sickness stops, Henderson notes you may still be contagious for up to two days after symptoms have passed. “It’s variable, but I always say assume you remain infected for about 48 hours after your symptoms have cleared,” he says.
The other key factor — to avoid spreading and catching the bug — is “scrupulous hygiene”.