Governments across the Asia-Pacific region are rushing to impose tougher lockdown measures to combat the spread of the highly infectious Covid-19 Delta variant.

The sudden resurgence of coronavirus outbreaks is straining health systems and stoking public anxiety about vaccination programmes plagued by delays and supply shortages.

Indonesia is among the worst-hit countries in the region. The nation of 270m faces its deadliest outbreak since the pandemic began, with its medical system struggling to cope with a record number of cases.

The daily death toll has doubled over the past week to more than 1,000 and authorities have warned that the number of new infections could surge as high as 70,000 after surpassing 34,000 on Wednesday.

Many hospitals have reached capacity and are already turning patients away. The government has resorted to importing oxygen tanks from neighbouring countries as supplies are exhausted.

Joko Widodo, the president, has extended lockdown measures in areas including Java, the main island, and Bali. But Jakarta has resisted imposing greater restrictions for fear of hurting south-east Asia’s biggest economy.

Indonesia has relied on Chinese Sinovac jabs, but the vaccination rate has been slow and beset by supply issues.

In Australia, authorities have warned that thousands of people could die unless an outbreak in Sydney linked to the Delta variant was brought under control. A two-week lockdown in the city of 5m has failed to quell a cluster of active cases, prompting a tightening of restrictions on Friday.

“We cannot live with this variant. No place on earth has unless they have their vaccination rates are much, much higher than what we have,” said Gladys Berejiklian, premier of New South Wales.

“Otherwise, it subjects the population to thousands and thousands of hospitalisations, thousands of deaths,” she added.

Australia and South Korea were among those countries that won international praise for suppressing the virus last year. While the death toll in these countries remains comparatively low compared with the US and UK, botched vaccination rollouts have left the public vulnerable to outbreaks.

South Korea on Friday instituted its highest level of virus-related restrictions across Seoul and the capital’s surrounding areas, affecting about half the country’s 52m people.

“We are facing the biggest crisis with our containment efforts with the daily new cases hitting a record every day,” said Kim Boo-kyum, prime minister, as he announced the latest lockdown.

The measures included bans on gatherings of more than two people after 6pm and shuttering schools.

Jeong Eun-kyeong, head of the Korea Disease Control and Prevention Agency, warned that the worst was yet to come despite signs that the vaccine drive was picking up pace.

Gen Paul LaCamera, who leads the 28,500 US troops stationed in South Korea, has also reintroduced tough controls on the movements of military personnel in response to the latest outbreaks.

“While we have achieved more than 80 per cent vaccination rate, we are witnessing small clusters of the virus’ spread within select locations,” LaCamera said.

A surge in cases in Japan forced Prime Minister Yoshihide Suga to declare a state of emergency in Tokyo on Thursday evening, which means the Olympics will be held largely without spectators.

Reporting by Edward White, Song Jung-a and Kang Buseong in Seoul, Mercedes Ruehl in Singapore, Jamie Smyth in Sydney and Robin Harding in Tokyo