The 1,340 Maluku Islands are a long way from anywhere. So remote are these Indonesian isles that the country’s most famous novelist was imprisoned there in a gulag that was actually an archipelago.

But the coronavirus is stalking the farthest reaches of the planet.

The first case of the virus in the Malukus was confirmed in mid-March: a hardware technician who had journeyed from Indonesia’s most populated island, Java. With the central government loath to impose a national lockdown, local officials took matters into their own hands, instituting quarantines and limiting flights and ferries.

It didn’t work. Twenty-five medical workers at one hospital in Ambon, the biggest city in the Malukus, have tested positive for the coronavirus, even though none had contact with Covid-19 patients there. A hat vendor with no history of travel to other Indonesian viral hot spots became sick and died in early May, signaling that community transmission had begun.

Over the past week in Maluku Province, positive coronavirus tests have increased by double digits each day, with limited testing — only around 600 people have been tested — surely obscuring the true caseload.

“We didn’t expect it to happen this fast,” said Kasrul Selang, the head of the coronavirus task force in Maluku Province. His wife has tested positive for the coronavirus.

The world’s fourth most populous country, Indonesia offers both a cautionary tale for how dithering leadership can thwart public health and a medical puzzle for why an unprepared nation’s hospitals have so far not been overwhelmed by the virus.

With thousands of islands straddling a section of the Equator wider than the continental United States, Indonesia has counted on its sprawling archipelago and youthful population to slow the deadly spread of the virus. But with sharp caseload increases in far-flung regions like the Malukus and full-blown outbreaks on more populated islands like Java, Indonesia’s luck may be running out.

In early May, Indonesia had recorded fewer than 12,000 cases of the coronavirus, with around 865 deaths. By Thursday, the number had increased to 24,538 confirmed cases and 1,496 deaths. Health experts say even this doubling of cases reflects the limits of testing rather than the true caseload.

In an alarming glimpse at what could be runaway transmission, a random sampling of 11,555 people in Surabaya, the country’s second largest city, found last week that 10 percent of those tested had antibodies for the coronavirus. Yet the entire province of East Java, which includes Surabaya, had 4,313 officially confirmed cases as of Thursday.

“Massive infection has already happened,” said Dono Widiatmoko, a senior lecturer in health and social care at the University of Derby and a member of the Indonesian Public Health Association. “This means it’s too late.”

Yet even as the country’s caseload accelerates, the Indonesian government has said that national coronavirus restrictions, already a scattershot effort, must be relaxed to save the economy.

“If people don’t eat and they get sick, it will be worse,” said Joko Widodo, the president, at a briefing for the foreign news media.

There is widespread concern among public health experts, however, that Indonesia’s health care system will break down if the coronavirus spreads as intensely as it did in the United States or Europe.

Worryingly, more than half of Covid-19 deaths in Indonesia were of people below age 60. In the United States, most deaths have been among the elderly. The relative youth of the victims in Indonesia, health experts say, hints at hospitals that are unable to provide the kind of lifesaving treatment offered in other countries.

And epidemiologists fear an even bigger surge in cases next month. Last week, in a country with the largest Muslim population in the world, millions of Indonesians gathered to pray and travel at the end of Ramadan, the Islamic holy month. In the capital, Jakarta, more than 465,000 vehicles left the capital during the holiday period, according to a toll operator.

While the Indonesian government announced some coronavirus travel restrictions in late April, they have not been enforced rigorously, critics say. Loopholes abound. Airport staff have complained about entire families, including children, flying under exemptions meant for business travelers.

Modeling by epidemiologists at the University of Indonesia forecasts that up to 200,000 Indonesians may require hospitalization for the virus because of Ramadan-related activity.

Achmad Yurianto, the spokesman for the National Covid-19 Task Force, said that he expected a surge in confirmed cases beginning next week because of all the holiday movement.

Because Indonesia’s testing rates are the worst among the 40 countries most affected by the virus — 967 per 1 million people, compared to 46,951 per 1 million people in the United States, as of Wednesday — Indonesians, especially those with asymptomatic or mild cases, are unknowingly spreading the virus, infectious disease experts warn.

“The disaster is still coming,” said Dr. Pandu Riono, an epidemiologist who led the University of Indonesia’s modeling effort. “Even after many months, we still have leaders who believe in miracles rather than science. We still have terrible policies.”

The Indonesian government should have known better. For weeks, even as nearby countries recorded spiraling local infections, Indonesia’s leaders acted as if the archipelago were somehow immune to the coronavirus.

“They were in denial,” said Dr. Erlina Burhan, a senior pulmonologist at Persahabatan Hospital in Jakarta. She noted that she has already been falling asleep in exhaustion at her desk because of the deluge of coronavirus casework.

Indonesia didn’t confirm its first coronavirus case until early March. Neighboring Malaysia and Singapore recorded their first cases in late January.

Meanwhile, some hospitals, particularly on crowded Java, were logging big upticks in pneumonia cases with symptoms similar to Covid-19. But bodies were buried before coronavirus tests were administered.

The governor of Jakarta said hundreds of people had probably died of Covid-19 in the capital but were not part of any official coronavirus count.

Denial continued among Indonesia’s top leaders, even as a cabinet minister fell ill in mid-March. The nation’s health minister suggested that prayer could ward off the virus. Or maybe exercise and vitamins could do the trick.

Mr. Joko, the president, eventually admitted that the true situation wasn’t being shared with the public to avoid panic spreading across the archipelago.

Because national restrictions weren’t put into place until about a month ago, some provincial officials instituted their own travel bans, just as state governors did in the United States.

In Maluku Province, the governor began limiting arrivals at the airport and big ports in late March, after the first case was confirmed there. About 6,000 outsiders were quarantined.

But in a notoriously corrupt country, not everyone followed the rules. Even if official ports of entry were monitored, fishermen moved back and forth from the Malukus to viral hot spots like Makassar on the island of Sulawesi, where infections proliferated after a gathering of a Muslim revivalist group.

For each place like Maluku Province that tried to impose local discipline, others were proceeding as if life were normal.

“If they had restricted movement since the beginning, the disease would not have spread to almost all over Indonesia,” said Dr. Rodrigo Limmon, head of the Ambon branch of the Indonesian Doctors Association.

In the Malukus, medical staff resorted to using plastic raincoats from convenience stores for lack of proper equipment. Ambon, which was devastated by communal violence at the turn of the century, has only 25 ventilators. The Haulussy Hospital, where the 25 medical workers tested positive, was forced to close.

“If they get sick or die, how will we survive?” said Wiesye Pelupessy, founder of an Ambon civil society group that has been distributing personal protective equipment for local medical workers.

Some officials are hopeful that, for now, the virus hasn’t spread to the farthest-flung islands in the Maluku island chain. The southeastern Malukus have not yet recorded a single case.

There are other, even more unlikely, places in Indonesia that have avoided out-of-control epidemics. The tourist island of Bali had direct flights from Wuhan, the Chinese city that was the center of the initial outbreak. Even in March, holidaymakers were arriving in Bali from Europe and other places hard hit by the virus.

Yet Bali has had just 420 confirmed cases. Gusti Ngurah Mahardika, a virologist at Udayana University in Bali, checked in with local crematories to see whether more bodies were coming in because of the coronavirus. They were not.

“It is not the Indonesian habit to hug and to kiss,” he said, looking for possible factors that might have contributed to the island’s low caseload. The same cultural social distancing has been mentioned in connection with the relatively low number of infections in countries like Japan and Thailand compared with Brazil or Italy.

Nevertheless, public health experts in the Malukus are bracing for what many fear will be a new wave of cases following the post-Ramadan festive period. Over the weekend, local markets were packed with holiday shoppers.

Despite local government regulations limiting spiritual worship, the faithful flocked in Ambon last Sunday to celebrate the end of Ramadan. Few wore masks. So far, most of the region’s biggest outbreaks have been linked to superspreader religious events.

“In Maluku, we are lucky that we are islands,” said Meikyal Pontoh, the head of the provincial government health office. “But because this is already worldwide, we have to fight really hard and pray really hard.”