Sprayed, sniffed and searched in Sydney

It's been a long flight and the Olympics and outback await, but the most vigilant quarantine officers in the world stand between you and Australia.

They may stand between you and the airport in fact, barging right onto the plane, disinfectant spray in hand, spraying you and your belongings with a fine mist of insecticide.

Don't worry -- it's not you they object to. It is the mosquito in the overhead bin, the dirt on your tennis shoe, the salami in your sandwich, the grapevine in your baggage.

"It might not seem like the most welcoming arrival, but it is done for very good reason, and the spray is a World Health (Organisation) approved mixture," said Carson Creagh, spokesman for the Australian Quarantine and Inspection Service.

"We're trying to protect the very things that appeal to people from other countries about Australia -- the wildlife, which just doesn't have any resistance to exotic diseases, and the environment, because there are many plant diseases out there that could devastate Australia."

Every aircraft arriving in Australia is sprayed with insecticide disinfectant, and every passenger questioned about their belongings -- no animal, food, plant, or soil is allowed.

Creagh said regular flights from Europe and North America are sprayed before passengers board -- the better to avoid complaints from indignant passengers who object to flight attendants or quarantine officers hand-spraying them on arrival.

But planes from Hawaii, southeast Asia, tropical South and Central America or tropical Africa are considered high-risk for carrying exotic pests, so the plane is boarded and the cabin sprayed before anyone is allowed out.

Passengers flying from Los Angeles or London should not assume they will spared. The quarantine service would rather be safe than sorry, so short flights, carriers new to the route, or planes not usually used for Australia may be hand-sprayed too.

Creagh said Australia has been spraying arriving aircraft since the 1960s -- and is just one of 65 countries that does.

But the others, which include Brazil, China, France, India, New Zealand, and South Africa rely on residual insecticide that is sprayed before passengers board.

The spray, a synthetic insecticide called permethrin or d-phenothrin, is based on the same naturally occurring chemical produced by plants to kill predatory bugs.

People sometimes react to the propellant in the spray, Creagh said, but the insecticide itself is harmless to humans.

Mosquitoes, potential carriers of malaria, dengue fever and Japanese encephalitis, are the main target.

Creagh said the classic case that preys on the minds of quarantine officers is that of a man who had never been outside Switzerland, yet died of tropical cerebral malaria.

"It was found that he lived a kilometre or so from an international airport and unfortunately a mosquito survived a flight from west Africa, got off the plane feeling tired and thirsty and a bit jet lagged and bit this guy."

It's not just the mosquitoes Australia is after, but also the snacks you've brought along. Fruit, meat, dairy, nuts and eggs -- to name a few -- will be confiscated on arrival.

Taking people's food is a delicate matter, Creagh admits.

"People would often like to bring familiar foods with them. Advertising is partly to blame for this, because Australia is marketed as the last frontier, the home of Crocodile Dundee. And there are many people who come to Australia concerned that they won't be able to buy ordinary food."

It's a blurred line. Chocolate bars are okay, and candy gets a pass. But cereal bars -- which may contain both fruit and nuts -- are not allowed. The nuts in chocolate bars are okay.

Creagh said there are a couple of ways around the rules.

"We've had examples of people who have presented goods for inspection and been told they can't bring them in, so they have elected to eat the whole lot then and there," he said, recalling a South African who consumed "a considerable amount" of beef jerky in front of quarantine officers.

In other cases it is possible to irradiate the food or to heat treat it -- though understandably not always the ideal solution. If it is not a food item, it can be fumigated.

And if the salami from grandma slips your mind and goes undeclared, Australia has 31 detector dog teams on hand to jog your memory -- a dozen at the Sydney airport alone.

Don't expect snarling German shepherds -- these security canines are the humble beagle made famous by Snoopy.

"The beagles are trained to respond to 32 target odours, these include meat, plant material, fruit, bird eggs, live birds, reptiles, all sorts of things. And they walk around among the passengers in the baggage hall and the baggage carousels and they sniff the luggage," Creagh said.

In the vast majority of cases, Creagh said, undeclared items are an innocent mistake. But if the concealment was deliberate, fines can range from A$55 (US$32) to A$10,000 (US$5,794) -- or up to five years imprisonment.

Ideally, there are no hard feelings.

"We've had the odd occasion when people have been fined and they actually patted the dog and congratulated it on its sense of smell," Creagh said.