SYDNEY (BLOOMBERG) - Australia is on high alert for foot-and-mouth disease in its cattle herds after traces of the virus were found on imported animal products.

The disease is already ripping through Indonesia, and is creeping ever closer to paddocks Down Under, where an outbreak could spell disaster for the livestock industry, the economy and world beef supplies.

What is foot-and-mouth disease?

Foot-and-mouth disease (FMD) is a highly contagious virus that affects cattle, sheep, goats and pigs. It is characterised by fever and blister-like sores on the tongue and lips, in the mouth, on the teats and between the hooves.

The prevalence of the disease has the potential to decimate herds. The disease is often spread by humans via their shoes, clothes and luggage - and particles can even live in people's noses, where they may survive for up to 24 hours.

The virus can also be transmitted via contaminated meat and other animal products, and survive in the environment for several weeks.

It is considered one of the most important livestock diseases in the world, and can potentially cause billions of dollars of losses each year.

Can humans catch it?

Although the virus comes from the same family - Picornaviridae - as those responsible for common colds, hepatitis A and polio, foot-and-mouth disease crosses the species barrier to infect humans only rarely and with little effect.

It shouldn't be confused with the fever and rash-causing hand, foot, and mouth disease in humans. This is an unrelated and usually mild infection mostly in children caused by different viruses, mainly coxsackie A and enterovirus 71.

Where is it a problem now?

The World Organisation for Animal Health says the disease is endemic across swathes of Asia, and most of Africa and the Middle East. Right now, there's growing concern over the spread in Indonesia after the country reported the disease in May and the virus swept through the nation's cattle herds.

Surrounding nations like Australia are particularly alarmed at the proliferation of the virus, which has reached the tourist hot spot of Bali. Each month, thousands of Australians return from holidaying on the island. New Zealand, which has a large livestock population, also remains on high alert.

What's being done?

Australia has offered Indonesia funding for one million vaccines to curb the spread there, and within its own borders it has ramped up surveillance and counter-measures - including educational videos and sanitation foot mats at airports. Some politicians have gone even further by calling for a suspension of travel to Indonesia, but that's been rejected by officials.

The threat of incursion is greatest on imported animal products, according to Agriculture Minister Murray Watt. Traces of the disease have been found in a sample of pork floss that was being offered for sale in Melbourne, though the test did not indicate a live virus.

Is there a threat to global beef supplies?

An outbreak of the disease would pose a serious threat to Australia's A$32 billion (S$30.8 billion) livestock industry, and a widespread occurrence could have an estimated direct economic impact of A$80 billion.

Though Australia accounts for only 4 per cent of global beef production, the country is a top shipper - comprising about 13 per cent of world exports.

Depending on the extent of any potential spread, an outbreak could result in the culling of animals. Authorities may deploy vaccines to contain the virus, but such a strategy often leads to a longer imposition of trade restrictions in FMD-free countries with Australia prevented from accessing overseas markets.

Either move is likely to dent Australian export volumes to some degree, and major markets in China, Japan and South Korea could see the most impact. An outbreak would also taint Australia's export reputation, and the effect could linger for years after livestock herds recover from the disease.

Has this happened before?

It has. Britain was forced to destroy millions of cattle and sheep to contain foot-and-mouth two decades ago.

The economic cost to the agriculture and food industries was substantial, with losses estimated to have exceeded £3 billion (S$5 billion) at the time. The outbreak triggered restrictions on the country's meat exports and access to the countryside was curbed for visitors.