BANGKOK — For months, many Southeast Asian countries played down the threat posed by the new coronavirus. Some officials said that prayer would keep the disease away. Others expressed optimism that the tropical heat would slow the spread of the virus.
Life continued as usual. Malaysia allowed large religious gatherings. Thailand kept open its hugely popular Muay Thai boxing stadiums. In countries with struggling health care systems, like Indonesia and Myanmar, testing for infections was minimal.
Now, with the belated realization that the virus is encircling the globe in its relentless spread, countries across Southeast Asia have begun to impose strict measures, including lockdowns in the Philippines and Malaysia and the widespread closure of schools, businesses and entertainment venues in Thailand. The delays are proving dangerous, as some nations face a worrisome rise in cases without a health care system that can deal with a major outbreak.
The Indonesian president, Joko Widodo, has admitted that he misled the public about the dangers of the disease caused by the coronavirus, Covid-19, to prevent people from panicking.
“There is that which we disclose and there is that which we withhold because we do not want to create worry and panic among the society,” he said on Friday.
Mr. Joko refused on Monday to disclose the results of his own test for the virus, telling reporters to ask his doctor.
The Indonesian transportation minister, Budi Karya Sumadi, has tested positive, and as many as a dozen other officials have been tested for infection.
Mr. Joko declined to disclose those results, too.
The spokesman for the coronavirus emergency response in Indonesia, Achmad Yurianto, would not provide the results on Tuesday, either, saying only that the officials “are in good condition so far.”
Transparency has generally been a concern.
Health officials on the island of Bali said they learned that a British woman being treated there had tested positive only after officials in Jakarta, the Indonesian capital, announced her death to the news media.
Before that, the first two patients with confirmed infections discovered that they had contracted the virus when the president announced it to the country.
In the Philippines, critics have accused President Rodrigo Duterte of using the virus as cover to pursue his oft-stated ambition of imposing martial law.
“Whatever his personal preferences, the president should not consider authoritarian methods,” said Etta Rosales, a former chairwoman of the Commission on Human Rights in the Philippines. “Authoritarianism is no cure to the virus.”
After Mr. Budi, the Indonesian transportation minister, tested positive, Mr. Joko became more attuned to the problem, ordering the closure of schools and encouraging residents to work from home.
Other countries remain in denial about the dangers of the virus. The chief spokesman for the Myanmar government said on Friday that the absence of positive tests was proof that the virus has not reached Myanmar.
“Covid-19 is still not present in Myanmar,” the spokesman, U Zaw Htay, told reporters. “The lifestyle and diet of Myanmar citizens are beneficial against the coronavirus.”
Some Buddhist figures have been promoting nonmedical remedies. One famous monk said that eating a lime and three palm seeds would keep the virus away. Another monk recommended seven ground peppercorns.
Even some doctors are optimistic that the pandemic will bypass Myanmar because of its religious practices.
“Myanmar is still lucky because it’s a Buddhist country and senior monks are always praying to be safe,” said Dr. Win Thandar Phyu, the chief of North Okkalapa General Hospital in Yangon.
The concern is that the lackadaisical approach has allowed the virus to spread largely unnoticed, setting the stage for a disaster in countries where the health care systems are underfunded and poorly equipped.
Indonesia’s rate of testing has increased in recent days, but it is still one of the worst in the world, about 8.5 tests per million people. The first positive patient was detected on March 2. Now, it has confirmed 172 cases.
In a letter to the president, an association of scientists called the Indonesian Young Scientist Forum pressed for immediate action. The group pointed out that confirmed cases have grown at an exponential rate since early March.
“Indonesia is in a dangerous situation because the delayed action to halt the spread of the virus makes it difficult to control,” the scientists said. “The delay could make the epidemic situation similar to Italy and Iran or even worse.”
Some countries are seeing a rapid rise in the number of confirmed cases.
Many are connected to an international gathering of 16,000 Muslims early this month in the Malaysian city of Selangor. Participants returning home have taken the illness with them to Singapore and Brunei, where nearly all of its 40 cases were linked to the meeting of the revivalist missionary movement, Tablighi Jamaat. An additional 700 participants returned to Indonesia, where there has been no effort to track them.
Malaysia has seen a surge in cases tied to the event. On Monday alone, 95 of 125 new cases were connected to the event. It now has 673 cases.
The World Health Organization urged nations in Southeast Asia to adopt aggressive measures as the number of confirmed cases rises.
“The situation is evolving rapidly,” Dr. Poonam Khetrapal Singh, the director for WHO’s Southeast Asia region, said Tuesday. “We need to immediately scale up all efforts to prevent the virus from infecting more people.”
Several countries are now scrambling to impose the kinds of travel restrictions and quarantines seen in other parts of the world.
In the Philippines, about 60 million people — more than half the country’s population — are under lockdown. In Malaysia, mass gatherings are banned through the end of the month; schools, businesses and places of worship are closed; and Malaysians are prohibited from leaving the country. In Thailand, the prime minister announced the postponement of Songkran, a festival that is held each April to mark the Thai new year.
But for Indonesia, which is already playing catch-up, dramatic action like that of its neighbors appears to be off the table.
“Lockdown is not an option,” said Mr. Achmad, the Indonesian spokesman.
Reporting was contributed by Hannah Beech and Ryn Jirenuwat from Bangkok; Muktita Suhartono and Dera Menra Sijabat from Jakarta, Indonesia; Saw Nang from Mandalay, Myanmar; and Jason Gutierrez from Manila.