But through comprehensive testing, tracing, and quarantining in centralised facilities, and strict border control and proactive public health policies, Vietnam defied all expectations and eliminated community transmission.

While many countries were enduring protracted lockdowns and reporting thousands of deaths per day, Vietnam was open for business, internally at least. It was the only economy in Southeast Asia to experience positive economic growth in 2020. By April 2021 Vietnam had reported just 35 COVID-19-related deaths.

Vietnam’s success can be attributed to good public health, focusing on prevention rather than costly medical cures. But with low rates of infection, there was little urgency to procure expensive new vaccines from abroad.

The government baulked at the cost and the length of the queue and went on record to say it would be better to produce vaccines domestically. Seeing an opportunity to establish a valuable foothold in the biotech sector, Vietnam invested in four indigenous vaccines. Tran Van Phuc, a medical commentator for one government newspaper, wrote in December 2020 that ‘it might come out much more slowly than its international peers, but if we can do it, waiting for a homemade vaccine is not a bad option’.

In December 2020, while other countries in the region fought to secure vaccine imports, Vietnam commenced a phase I trial on its most promising product to date, the subunit vaccine Nanocovax.

Progress was slow, but few were worried. The country had already successfully supressed two outbreaks and in February and March 2021, it would suppress a third, all the while developing superior testing and healthcare infrastructure.

Throughout this period the Vietnam government formally committed to just one foreign vaccine, Oxford-AstraZeneca. It initially secured 30 million doses to be delivered in batches throughout 2021 — enough to vaccinate just 15.5 per cent of the population.

The first batch of 117,600 doses arrived late February and was distributed to priority groups reflective of Vietnam’s ‘zero COVID-19’ standing. Healthcare workers, customs officers, diplomats, military personnel, police, tourist workers and teachers were given higher priority than people over 65 or those with chronic health problems at the highest risk of dying from the virus.

The emergence of the Delta variant in Vietnam at the end of April 2021 changed everything. The World Health Organization estimates that Delta is 55 per cent more transmissible than Alpha, which was itself around 50 per cent more transmissible than the original virus. Interventions that previously curbed community spread became inadequate to control outbreaks.

Initially, Vietnam managed to suppress localised outbreaks of Delta in Hanoi and Bac Giang province. Yet, despite escalating restrictions, cases continued to increase across the country. Between late April and late July 2021, Vietnam recorded over 120,000 cases in 61 of its 63 localities and over 800 deaths, Ho Chi Minh City being the worst affected.

This outbreak, and a shortfall in AstraZeneca supply, forced a rapid change in vaccine policy. Within weeks, Sputnik V, Pfizer-BioNTech, Moderna, Sinopharm and Johnson & Johnson were approved for emergency use.

Through swiftly negotiated contracts, foreign aid and the global vaccine access mechanism COVAX, Vietnam has now successfully ordered 125 million doses as it strives to vaccinate 70 per cent of its population by May 2022.

Earlier reluctance to enter the global vaccine market has meant Vietnam is further back in the queue than its neighbours, and most promised doses won’t arrive until at least the last quarter of this year.

While cases mount, vaccine rollout proceeds at a glacial pace. Vietnam lags behind all other ASEAN member states. By late July 2021, just 0.5 per cent of the population are fully vaccinated and 4.7 per cent have received one dose, in contrast to Cambodia with a single-dose rate of 42 per cent, and both Thailand and Indonesia at over 16 per cent.

Until recently the issue was strictly supply, but a succession of donations in July — while the health service scrambled to deal with its first major outbreak — has seen doses pile up. Vietnam has used only 5.3 million of 14.8 million doses received so far.

Once distributed, uptake appears to be good. The government earned trust from its earlier successful handling of the pandemic, and there is little of the anti-AstraZeneca sentiment which has hampered vaccine rollout in Australia.

As the health crisis escalates, vaccine priority is changing. Doses originally earmarked for tourist workers on Vietnam’s islands are being directed to older, vulnerable populations in the worst-affected locations, prioritising saving lives over rebooting the tourist sector.

In coming months, Vietnam will commence manufacturing Sputnik V and, thanks to a progressive technology transfer from the United States, construction has started on a factory that aims to produce a further 200 million vaccine doses in the first half of 2022. Vietnam’s Nanocovax has also entered phase III trials, raising hope for domestic self-sufficiency in years to come.

But with the Delta variant now firmly established, the economy strangled by lockdowns, and the health system approaching capacity, Vietnam needs to prioritise import and distribution of existing vaccines above all else. Millions of lives and livelihoods depend on it.

Barnaby Flower is a Clinical Research Fellow at the Oxford University Clinical Research Unit, Ho Chi Minh City.