If you absolutely have to throw up, New Zealand is one of the most barf-friendly places to do it. Puking is fast becoming one of the national pastimes. There are the infamous Cook Strait¹ ferries - there's a good reason why the seagulls in the TV advertisement are facing into the wind at the bow; only tourists go downwind. The teenage binge-drinking, so evident at New Year, which is part of a New Zealand tradition that goes right back to the 'six o'clock swill'², known affectionately as the 'six o'clock spill', and New Zealand may also be the campylobacter³ capital of the world.

New Zealand may not have hosted the most celebrated instance of spewing, probably when American President George Bush once launched Operation Dessert Storm by projectile vomiting all over the Japanese Prime Minister at a state dinner, but when they say New Zealand is a great place to bring up a family, they do mean bring up. Kiwis have more words for chundering, hurling, producing technicolour yawns and making a long-distance call on the great white telephone than the Inuit have for snow. Many of those not born there will recall being stunned when first hearing the typical New Zealand-accented compliment to the chef, 'That looks spewful, Dear!'. Much, much later, it clicks... it's 'That looks beautiful'. However, that first impression is not entirely wrong; the New Zealand Medical Journal reports that the estimated number of cases of foodborne infectious disease is approximately 119,000 a year, resulting in around 497,000 lost days work at a cost of NZ$88.8 million. The total number of cases of all infectious intestinal disease could be as high as 823,000. This is no mere splash in the pan.

Notorious University Student Pastimes

But the old 'Chunder Mile' days at university have gone. Massey, once notorious for its Tour de Coma cycling pub tour and its Soak Days (where less nimble students were covered in vomit), now has a Safe Drinking Promotion Committee. Waikato now has chilli-eating competitions instead of keg-skulling sessions - there's still a rush for the loo, but the upchuck is nowhere as bad as in one orientation week incident when the 'pavement pizzas' were an inch thick on the floor.

The legendary stories of Otago students retching for records include the one about the med school flatmates who drank homebrew until everyone threw up. In the morning, one of the students - now a top doctor - awoke with a headache like a tight band around his forehead. The prospect of daylight was painful, but when he finally did dare to open his eyes everything was blank. Total whiteness. 'God!' he screamed, in panic, 'I've blinded myself with alcohol poisoning!' Then he realised that he had passed out with his head upside down in the toilet - his hair just reached the water level - and all he could see was the porcelain bowl.

Projecting Viral Particles

Community nurses encourage babies who 'bubble up' after nursing. That has to be quickly unlearned; belching and throwing up in adults are taboo. The Romans, of course, would commonly throw up during a meal to make room for more, but there is now increasing recognition that the last place you want to be is near someone vomiting with the classic summer tummy-bug Norwalk-like Virus (NLV). Dr Greg Simmons, an Auckland public health physician and spokesperson for the Foodsafe Partnership, points to new research about the spread of NLV. It is estimated that more than 30 million virus particles can be liberated during vomiting and, in susceptible adults, just one viral particle has the risk of illness of about 21%.

The research highlights the case of six parties of diners, totalling 126 people, attending an evening dinner at a large hotel in December 1998. At 8.30pm, during the meal, a woman diner vomited onto the polished wooden floor. The vomiting was not projectile and none of it was thought to have made contact with the table. The vomit was rapidly cleaned up by one of the waiters with a mop and disinfectant and the meal continued. 52 of the diners later reported illness. The attack rate of the infection was directly proportional to the distance from where the woman was seated. The evidence strongly suggested, says Simmons, that there was airborne transmission of NLV from the woman who had vomited, leading to inhalation and subsequent ingestion of the virus by the other diners.

Close the Door and Open the Windows

So what do you do if someone with a tummy bug vomits near you? 'Close the door and open the windows to the outside', says Simmons.

Get the air flowing away from people around. And use a household bleach in a reasonably strong solution to get rid of the virus on surfaces... Once someone is vomiting, drinks such as lemonade can actually make dehydration worse because they contain too much sugar. Cold boiled water is often better.

Remember, Club Emesis, a medical group that studies vomiting in humans, reminds us that vomiting is 'nature's way of reminding you that what you did to get sick in the first place wasn't good for you'. If nothing else, it's a reminder to never again mix margaritas and lager.