A study has warned that without action almost a quarter of a million Indonesians could die from COVID-19 by the end of the month.

Key points: Indonesia has reported 1,528 cases of COVID-19 but experts say the number is likely much higher

Indonesia has reported 1,528 cases of COVID-19 but experts say the number is likely much higher A new study has projected coronavirus deaths in Indonesia could reach 240,000 by the end of April

A new study has projected coronavirus deaths in Indonesia could reach 240,000 by the end of April Bali and other provinces have implemented their own lockdown procedures ahead of national authorities

The warning came after President Joko Widodo declared a national public emergency on Tuesday.

While he shied away from implementing a total lockdown in response to the coronavirus pandemic, Mr Widodo imposed "large-scale social restrictions", granted police additional powers and announced a $40 billion economic stimulus package.

The Government also announced all foreign nationals except for diplomats, humanitarian workers and those with residency permits would be barred from entering Indonesia for 14 days.

But John Mathews, an epidemiologist from the University of Melbourne, told the ABC the measures had come too late.

"If they were able to effectively close their borders a month ago, they should have done so," he said.

"In a sense, the horse has bolted now."

Given the population density and poverty in the country of 270 million, he said, "controlling [the virus] in the social circumstances in Indonesia will be very difficult".

Infection numbers likely higher than official figures

Indonesia's national health ministry says the total number of cases has climbed to 1,528, about half of which are in the capital Jakarta.

At least 136 people are dead.

However modelling suggests the true number of infections across the archipelago is in the tens of thousands.

A new study released by the University of Indonesia projected that without intervention, the country could see more than 240,000 deaths by the end of April.

Even with moderate intervention, 48,000 Indonesians could die, but the number could be lowered to 12,000 with "high-intensity intervention", the study found.

The news came as the White House projected between 100,000 and 240,000 could die in the US, even with physical distancing.

In 2017 the World Bank found Indonesia only had four doctors for every 10,000 people. It is estimated to have less than three intensive care beds per 100,000.

"They're working under very difficult circumstances," Professor Mathews said.

"You'd really have to assume there are many cases that are not known about and likely a number of deaths."

While a law was enacted on March 19 which banned mass gatherings nationwide, some citizens have continued to ignore social-distancing requirements.

Police have been forcibly shutting down weddings and other events that have proceeded despite the prohibition.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 1 minute 3 seconds 1 m 3 s Police in Jember, Indonesia, shut down a wedding reception amid the COVID-19 pandemic.

Local media have reported that police intervened to prevent religious gatherings in Tangerang, a satellite city of Jakarta, and were urging people to report any similar events to authorities.

In neighbouring Malaysia, many cases stem from an Islamic gathering of some 16,000 people in Kuala Lumpur in February.

After the event, attendees returned to Indonesia, Brunei, Thailand and the Philippines.

The quasi-governmental Indonesian Ulema Council (MUI) later issued a fatwa, declaring mosques should be closed to avoid further spread of the disease.

Muhammadiyah, Indonesia's second-largest Muslim organisation, this week called for the devout to avoid participating in special night-time prayers during Ramadan, which begins in late April.

A local Disaster Mitigation Agency officer sprays disinfectant on a mosque in Surabaya during the coronavirus pandemic. ( Reuters via Antara Foto/Zabur Karuru )

Indonesia stepping up coronavirus response

Indonesia is beginning to increase measures to slow the spread of the virus.

Mr Widodo last week inaugurated a specialist COVID-19 hospital in Jakarta capable of treating 3,000 patients.

And the Government is constructing a hospital on Galang Island, off Sumatra, dedicated to treating people infected with COVID-19.

Indonesia has turned the 2018 Asian Games athletes' village into an emergency medical facility with a 3,000-bed capacity. ( AP: Hafidz Mubarak A )

In addition, authorities are set to release about 30,000 prisoners to avoid the rapid spread of the disease in overcrowded jails across the country.

This represents around 11 per cent of the national prison population, according to the Jakarta-based Institute for Criminal Justice Reform, which welcomed the move but called for the release of greater numbers of non-violent offenders.

But critics say citizens' failure to observe physical-distancing restrictions can be attributed to the Government's slow response to the pandemic early on.

"When other countries were already issuing red alerts to deal with the COVID-19 outbreak, our Government did not seem serious," Yanuar Nugroho, an academic and former adviser to Mr Widodo, told the ABC.

"The capacity of the Government in dealing with this crisis is truly questionable."

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The administration of Mr Widodo, who was re-elected last April, has been seen to be prioritising the economy over the public health emergency.

Indonesia only reported its first cases of COVID-19 on March 2.

Health Minister Terawan Agus Putranto, a devout Christian, then attributed a supposed lack of cases to the country's penchant for prayer.

The Home Affairs Minister, meanwhile, suggested people could avoid coronavirus by eating bean sprouts and broccoli because they are high in vitamin E.

Mr Widodo himself has promoted drinking jamu, a traditional herbal drink believed to have medicinal properties.

Mr Putranto has since faced a barrage of criticism and calls to resign for his management of the crisis.

The WHO has advised Indonesian authorities not to spray disinfectant onto people's bodies. ( AP: Tatan Syuflana )

And the President admitted earlier this month authorities had withheld information from the public to "avoid panic".

The World Health Organisation, meanwhile, has publicly called for Indonesian authorities to stop spraying disinfectant directly onto people's bodies.

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The agency's Indonesian representative Navaratnasamy Paranietharan said the practice was not helpful and could in fact be harmful to people's eyes and mouths.

It was also announced this week Indonesia had become a member of the Solidarity Trial, a global WHO initiative to test vaccines across various countries.

Local governments take matters into their own hands

As in Australia, local authorities across Indonesia have implemented tougher prevention measures than the central Government, despite Mr Widodo's requests for them to only act in accordance with directives from the national COVID-19 task force.

Bali's provincial authorities have declared a state of emergency under which all people entering the island, including Indonesians, are forced to self-quarantine for two weeks.

Last month, the Mayor of Tegal in Central Java announced he was shutting off the city to prevent the spread of COVID-19, including by building concrete barriers across roads leading into the town.

"I'd rather be hated than have my citizens die," he said.

Jakarta Governor Anies Baswedan announced a state of emergency on March 20, telling all commercial offices and entertainment venues to remain shut for at least two weeks.

Indonesia's congested capital is all but abandoned. ( AP: Dita Alangkara )

The ultraconservative, semi-autonomous province of Aceh banned foreigners altogether prior to the national Government.

But given that many Indonesians' sources of employment are informal and cannot be done from home, Mr Widodo has emphasised that physical distancing, rather than strict lockdown procedures, remain the most suitable approach.

"Every country has a different character, has a different culture, has a different level of discipline," he said last week.

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