Deadly swine fever is closing in on Australia's pork industry as experts say it has reached Indonesia.

The disease, although harmless to humans, could wipe of Australia's $5.2billion pork industry.

Indonesian authorities say the swine fever has been discovered in North Sumatra and has prompted experts to investigate any livestock deaths in the country.

In a press conference on Thursday, Bridget McKenzie, Australia's Agriculture Minister raised concerns about the disease.

She said that $66.6 million was being used to prevent the disease from spreading to Australia and the 36,000 jobs in the industry.

She asked that Australians travelling back from Indonesia be 'extra diligent' when declaring what they are bringing into the country.

Thousands of pigs have died in more than a dozen regencies across North Sumatra over the past three months, and the pace of deaths is increasing, authorities said.

'Every day, between 1,000 and 2,000 pigs are dying. It's quite a high figure,' said Agustia, the veterinary office chief in Medan, on Friday.

Still, he added that the current death toll was a small fraction of the 1.2 million hogs in North Sumatra, a part of Muslim-majority Indonesia that is predominantly Christian and where pork is an important part of local fare.

Last month, more than 1,000 cholera-stricken pigs were buried in the province after their decaying carcasses were plucked from local waterways, as police searched for suspects who discarded them.

Previously, lab tests found that the animals died of hog cholera but officials said they are also testing to see if any were infected with African swine fever. Neither are believed to pose a risk to humans.

In 2017, a hog cholera outbreak in Indonesia's East Nusa Tenggara province killed more than 10,000 pigs, causing severe financial losses for local farmers.