Experts have cast doubt on claims by Indonesian officials that they have not recorded a single case of foot-and-mouth disease (FMD) among Bali's cattle population in weeks.
Bali's Agriculture and Food Security office claims the island has been free of FMD for almost two months.
The last officially reported case in Bali was on August 1.
But the ABC has seen and filmed cattle with clear signs of FMD this month in separate areas of Bali.
Farmers have reported cattle with symptoms consistent with the disease, including foaming at the mouth, poor appetite and swollen feet.
And officials in Denpasar have also confirmed to the ABC that more than 60 cattle were slaughtered in the first week of September, because of the disease.
A senior Agriculture official says Bali slaughtered 556 cows with FMD in July, swiftly eliminated a small cluster of cases in Denpasar in August, and now has zero cases.
But one Indonesian virologist, who did not wish to be named, says he strongly doubts the claims that Bali is free of the disease.
And an Australian vet said it is not possible to eliminate FMD as quickly as Indonesian officials have claimed.
"I believe it's the second most infectious disease known to science," said Ross Ainsworth, a vet who has previously worked for decades in Australia's live cattle trade, and now spends considerable time in Bali.
"The policy of the government here is to not talk about the disease and hope that it will sort of fade from interest.
"It's just so infectious that it will be here and it will be here for a long time."
Bali also appears to be under pressure to eliminate the disease before the island hosts world leaders for the annual G20 summit in mid-November.
'We have zero cases. We really do have zero cases'
On a recent trip to Bali, the ABC recorded footage of cows in both the island's north-west and east that were displaying symptoms consistent with FMD.
However, many owners are not able to confirm a FMD diagnosis or arrange treatment because they cannot afford it.
At Jembrana in Bali's north-west, farmer Ketut Denio's cattle have been foaming at the mouth.
The thick white drool is a typical symptom of the highly contagious and potentially devastating disease.
But for cattle farmers like Mr Denio, euthanasia or even treatment by a vet is too expensive.
"The vet just took a look at one cow and gave it an injection because we had to pay for it ourselves," he told the ABC.
Across the road, another small herd shows similar signs of the disease: drooling, poor appetite and sore feet.
Farmer I Wayan Wilantara was worried his only cow might die.
But with no money to pay for a vet, he has administered a herbal mixture of turmeric and honey, and Betadine to sterilise the mouth.
"If I were to call the vet for three cows, that would cost me [$AUD15]," he said.
Despite the symptoms, local officials insist the cows in Jembrana are experiencing another, unknown ailment.
"We have zero cases. We really do have zero cases," said I Wayan Sunada, the head of Bali's Agriculture and Food Security office.
"I am certain. I am certain. I am certain it's not FMD. If we had reports of FMD we would go there and check."
Mr Ainsworth says there are other ailments that could cause symptoms such as foaming from the mouth.
"Alternative causes might include poisoning, oral foreign bodies, infection of the gums or tongue, intake of irritant chemicals," he said.
But those maladies are not usually coupled with foot lesions.
"It's very easy to differentiate by inspection of tongue and hard palate for blisters [or] ulcers and foot lesions and history of local FMD and vaccination history," he said.
The ABC has also seen and filmed more cattle with foaming mouths and foot lesions at Karangasem in Bali's east.
Karangasem was one of several regions confirmed to have had FMD in June and July this year, after authorities first detected it in Bali.
More than 60 cattle were also slaughtered in Denpasar in early September, with authorities there confirming it was because of the disease.
Yet, no cases in Bali have been officially reported to a national foot-and-mouth task force since August 1.
'If it was in Australia, it would be a cover-up'
The outbreak of FMD hit the island of Bali just months before it is due to host world leaders, including Australian Prime Minister Anthony Albanese, for the annual G20 meeting.
Agriculture officials have confirmed that a senior Indonesian minister, Luhut Binsar Pandjaitan, in late August gave a directive for Bali to achieve "zero cases" before the summit starts in November.
"Luhut told us that Bali has to be safe, has to have zero cases of foot-and-mouth," said I Wayan Sudana.
"We're working very hard to protect Bali."
Minister Luhut in August asked authorities on the island to take steps to control the movement of cattle in and out of Bali, to prevent any smuggling of livestock by land or through ports.
"Don't let Bali become a dangerous place that cannot be visited," he said.
Mr Ainsworth said the upcoming summit and earlier fears that Australia might close its borders to Bali to stop the spread of FMD, are reasons why Indonesia is trying to keep a lid on new cases.
"If it was in Australia it would be a cover-up," he said.
"In Indonesia, it's just good government policy. Things work different here than they do in the West."
How bad is the FMD situation in Indonesia?
The first outbreak of the highly infectious disease in Indonesia in 32 years was of great concern to Australia, which has been FMD-free since 1872.
Despite his fears that cases are still going undetected, Mr Ainsworth has praised the speed at which Bali officials are dealing with the disease, acknowledging that officials are vaccinating cattle faster there than in virtually any other Indonesian province.
Case numbers in Bali are undoubtedly low, given its entire herd is under 600,000 animals, spread sparsely among small family farms.
Families typically own just one or two cattle each as an investment.
As of this week, about 270,000 animals — or almost half the herd — has had at least one of two recommended doses of the vaccine.
Australia has supplied one million vaccines to Indonesia, most of which the ABC has been told are already being rolled out in Bali and islands further east where the disease is also spreading.
The islands of Sumba and Sumbawa are now classified as a "red zone".
But national figures suggest seven other provinces have also returned to zero cases, after previously reporting cases of FMD.
Despite initial fears the disease could reach Australia for the first time in 150 years, Ross Ainsworth believes the threat of the disease spreading from Bali is now much lower than it was.
"I initially was extremely concerned that this disease was going to get to Australia. I thought it was perhaps a 50-50 chance," he said.
"But now both of those things have changed. I think the threat is much lower."
Indonesia successfully eradicated an outbreak of FMD in the 1980s, largely through vaccination.
Mr Ainsworth says it is feasible that Bali at least, if not other provinces, could do so again.
"It was eradicated many years ago with vaccinations only. So maybe it's possible," he said.
