THIS has been a bad winter for norovirus; hospital wards have been shut, schools closed early and luxury cruises ruined. The toll has now topped one million.
Before Christmas, more than 400 passengers were affected on the cruise ship Oriana and it has now struck more than 200 passengers on the Queen Mary 2.
So what is the norovirus?
The name applies to a group of virus which include ‘Norwalk’. They probably account for half of all vomiting bugs worldwide.
The common name ‘winter vomiting bug’ gives a hint for what the bug does and when it attacks, although it can infect people at anytime of the year.
It causes up to one million cases in the UK a year and so it is hardly rare.
The virus is very infectious and spreads through what is euphemistically called the ‘faeco-oral route’.
To use less medical terms; it’s caused by people not washing their hands when they go to the loo.
But it can also be spread in the air after someone vomits.
In one outbreak among Scouts in the Netherlands it was found that every infected person infected an average of 14 others.
The only way to know for certain that a tummy bug is norovirus is to send a sample of stool to the lab.
As the treatment of norovirus is the same as for any other sickness and diarrhoea bug, there’s no point in sending a sample for everyone with the symptoms.
However, samples are sent in hospital patients or whenever there appears to be an epidemic.
It has been estimated that, for every positive test for norovirus, there are about 288 cases which have not been tested.
The illness often starts a few days after the person becomes infected.
The first sign of the bug is usually nausea followed by vomiting and watery diarrhoea.
It can give a high temperature, a headache and aching limbs.
Although you may feel awful, for most people it gets better by itself in a couple of days.
There is no specific treatment and most people fully recover with no lasting problems.
The Sun’s headline ‘Our vomiting hell on “plague” cruise ship’ was over-egging the pudding, although I would not recommend eggs or pudding with norovirus.
It might be helpful to take paracetamol to reduce the temperature and help the aching limbs.
The most serious risk is dehydration.
Again, for most healthy people severe dehydration is unlikely. Drink plenty of clear fluids.
We used to tell everyone to starve and only drink fluids but we now know that some food will do no harm but it is best to stick to something easy to digest such as soup, rice or pasta.
What you should not do is to go to your GP or the hospital A&E department.
There is nothing doctors can do and going out can risk spreading the virus. No one wants to be responsible for closing several wards.
The danger is for people who are elderly, young babies or anyone with another serious illness.
For vulnerable people, dehydration can be far more dangerous.
They are still infectious and so, if you are worried, ring the GP.
Luckily, the virus does not travel down a phone line.
Prevention is again obvious.
Anyone with symptoms of norovirus should stay at home for a few days.
There is no point is being a hero and struggling to work only to give it to your colleagues.
And anyone who works with food should have a stool sample checked before going back to work.
So the message is don’t panic, wash your hands, be scrupulous over basic hygiene and don’t go to the hospital or GP.
We now know that the Mayan calendar did not prophesy the end of the world. Neither does the norovirus.