Indonesia has become the latest country to confirm an outbreak of the deadly pig disease, African swine fever (ASF), that has wiped out more than a quarter of the world's pig population this year.

Key points: Indonesia has confirmed an outbreak of African swine fever in the province of North Sumatra late last week

Indonesia has confirmed an outbreak of African swine fever in the province of North Sumatra late last week Pig deaths in other provinces are being investigated

Pig deaths in other provinces are being investigated Travellers need to declare food products and have footwear cleaned at customs on return to Australia

Australian travellers to Asia are being warned not to bring back food and footwear that could risk our disease free status.

Australian Pork Limited's chief executive Margo Andrae said that returning travellers need to declare themselves to customs.

"Most importantly, just disinfect your shoes or, you know, if you don't need to bring your thongs back leave them over there," she said.

"When you come back into the country do not go near domestic piggeries, or if you have pigs in your backyard, please remember that you need to abide by Australia's biosecurity rules."

More than 80 percent of pigs infected with African swine fever die. ( Supplied: The Pirbright Institute )

The outbreak was confirmed in the province of North Sumatra late last week, with pig deaths in other provinces also being investigated.

ASF kills more than 80 percent of the pigs it infects, with no cure and no vaccine.

The disease spreads easily and rapidly, people going into an infected area can take the virus out on their shoes.

And the virus lives for up to two years in pork products, with fears it could enter Australia through infected products being brought in illegally.

How is ASF spread? It can spread when pigs come into contact with contaminated pigs, pork products, feed, ticks, and infected material such as syringes

It can spread when pigs come into contact with contaminated pigs, pork products, feed, ticks, and infected material such as syringes Pork products can carry the virus, even if they have been cooked or frozen

Pork products can carry the virus, even if they have been cooked or frozen Humans can transmit the disease if their clothing and boots have been contaminated by ASF, and they come into contact with uninfected pigs

Humans can transmit the disease if their clothing and boots have been contaminated by ASF, and they come into contact with uninfected pigs The infection can kill 100 per cent of the pigs

Biosecurity bolstered

Minister for Agriculture Bridget McKenzie said the news was concerning, with 188 flights a week from Indonesia directly into Australian cities.

"Bali is a favourite holiday destination for Australians and it's also a region with a lot of pigs," the Minister said.

"We have a zero tolerance approach to people who lie about what they have in their luggage and we've refused entry to Australia for six people caught with biosecurity risk material."

Australians caught bringing in pork products could face criminal prosecution or civil court action, and be ordered to pay up to $420,000 and be sentenced to up to 10 years in jail.

CSIRO researchers are using pig cells to understand how African Swine Fever works in order to develop a vaccine. ( ABC News: Jess Davis )

The Federal Government announced an extra $66 million dollars worth of funding last week, to boost biosecurity at Australia's borders.

That money will go towards 130 new officers at the border, more detector dogs and two new 3D X-ray machines at airports and mail centres.

Ms Andrae said that biosecurity had lapsed in the past and that this level of caution needed to become the new normal.

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"We are looking for long term sustainable funding to maintain this level at the borders," she said.

"Most importantly, we just want to get the message out to people to do the right thing."

New outbreaks of African swine fever have been reported in North Sumatra, Indonesia as at December 12, 2019 ( Supplied: FAO )

African swine fever has now spread to 11 Asian countries including: China, Mongolia, Vietnam, Cambodia, North Korea, Laos, Myanmar, The Philippines, South Korea, Timor-Leste and now Indonesia, according to the Food and Agriculture Organisation of the UN.