The unexpected emergence of a coronavirus cluster in the Vietnamese city of Da Nang has led to a rapid transmission across the country. Though previously lauded as a “success story” in the international press, having recorded no new local infections for 99 days, Vietnam has now detected cases in the capital, Hanoi, as well as Ho Chi Minh City, and throughout the Central Highlands region.

The first new case appeared in Da Nang Hospital on July 25, before the virus spread through the building, resulting in 15 confirmed cases over the next three days. The source of the cluster apparently remains unknown, though some government officials have claimed it originated outside the country. Vietnam has remained shut to most foreign travellers since late March.

The Health Ministry has registered 173 local cases since the new outbreak began, 120 of which were found in Da Nang. Besides the country’s two major cities, the virus has reached the provinces of Quang Nam, Thai Binh, Quang Ngai, Dak Lak, Dong Nai, and Ha Nam.

With 29 local cases discovered yesterday, the tally has grown to 620 infections, as well as five deaths, all of which were recorded since Friday. The victims were all elderly with pre-existing medical conditions.

Local newspaper Thanh Nien revealed the most recent death was an 86-year-old woman who suffered heart and kidney failure. She was admitted to Da Nang Hospital on July 16 and then transferred to a hospital in Quang Nam two days later. This suggests that she contracted COVID-19 in Da Nang at least one week before the first case was confirmed, and therefore that the virus had been circulating in the hospital undetected for a considerable time.

Nearly all of the cases last week were people above the age of 60. However, the 29 cases yesterday included a number of asymptomatic young people, including a 23-year-old health worker and four children below the age of 14. Due to the abrupt and widespread nature of the transmission, medical experts believe the real infection numbers may be far higher than the official figures.

Da Nang, a seaside resort, is a popular holiday destination for Vietnamese tourists on summer vacation. Since early July, over 800,000 people have visited Da Nang. The Vietnamese government fears that tens of thousands of tourists leaving the city after the cluster emerged could cause a disastrous transmission across the country.

On Wednesday, four days after the first case, a lockdown was established and checkpoints set up to prevent people from leaving or entering the city. Thousands of national police and military personnel were deployed in Da Nang, state-run paper Nhan Dan reported. By this time, however, thousands had already left the new pandemic epicentre.

Ho Chi Minh City had recorded 18,000 people returning from Da Nang on Tuesday. Hanoi has received around 54,000 returnees since July 25. Over 21,000 of these are suspected COVID-19 carriers waiting to be tested, as the city’s testing capacity is as yet unable to meet the large requirements.

Vietnam has 118 testing laboratories, of which only 66 are capable of testing samples for coronavirus. The nation’s capacity is 31,000 tests per day—a marginal increase on April’s average of 27,000 a day. But unless it dramatically expands, the testing could soon prove inadequate as the virus surges through a densely populated country of 97.3 million people.

In Da Nang, hospitals and health centres are fast reaching full capacity. Recently, a makeshift coronavirus hospital was installed inside a soccer stadium. The government has sent a contingent of more than 1,000 health workers to Da Nang.

Partial lockdown measures are being implemented in areas where coronavirus cases are appearing. Local authorities in Ho Chi Minh City have placed an apartment building under lockdown since Friday, as two residents had returned from Da Nang and were suspected to have the virus. The building houses 328 residents, but only 26 have been tested.

Tran Van Tan, Vice Chairman of Quang Nam province, imposed blockades on several rural villages and urban neighbourhoods, most of them overcrowded working-class districts. These include the Luu Minh residential area, in Thang Binh district, with 96 households and 384 people. Ostensibly under lockdown because of three confirmed cases there, no testing has yet been organised. With social distancing all but impossible in such locations, they will inevitably become incubators for the virus to grow.

It is now over a week since the Da Nang cluster surfaced, yet the Vietnamese government is reluctant to close businesses and halt production, despite the rapid spread of the virus.

Hanoi has closed its bars and roadside stalls and banned large gatherings. Restaurants and shopping malls, on the other hand, are permitted to remain open. Factories and other large-scale production facilities will continue to operate.

Prime Minister Nguyen Xuan Phuc’s warned on Wednesday that every province and every city was at risk. “We have to act more swiftly and more fiercely in order to control the outbreak,” Phuc told an online conference of government officials.

Ho Chi Minh City Party Secretary Nguyen Thien Nan also expressed concern that the situation is becoming far worse than the country’s first wave of infections, pointing to similar resurgences in Italy, Hong Kong, and Australia.

After suspending international travel on March 22, and introducing restrictions, Vietnam appeared to have contained the coronavirus. Like its counterparts in other countries, the government pushed ahead with a reopening policy to reverse the economic damage, particularly focussing on the revival of domestic tourism.

On June 1, the Vietnamese Ministry of Culture, Sports, and Tourism launched a new program aimed at galvanizing domestic tourist demand. The result was that people flocked to Da Nang from June onward, drawn by discounted flights, hotel bookings, and travel deals.

As with other Southeast Asian nations, Vietnam is heavily dependent on its tourist sector. The renewed spread of the virus is being viewed by the government primarily as a setback to their plans to reopen international travel and address the slowing economy.

In a report released on Thursday, the World Bank assessed that Vietnam’s economy would grow at around 2.8 percent in 2020, its slowest rate in 35 years and significantly lower than pre-pandemic levels. This finding, moreover, was based upon the situation before the resurgence in Da Nang.

Desperate to reverse the slowing economy, Prime Minister Phuc on Saturday approved the development of the country’s “night-time economy.” It will allow non-essential activities to occur overnight in major tourism zones and cities, many of which have witnessed new COVID-19 cases. Night markets, discos, karaoke parlours, retail stores, public transport, and other services are expected to generate profits unimpeded, despite the immense risk of accelerating the spread.