Cluster has grown to 148 people, with experts saying it could grow to 1,000 and take four to six weeks to stamp out

New Zealand is bracing for its biggest coronavirus outbreak yet as cases rise, the locations of interest balloon to more than 400 sites, and the number of close contacts swells to more than 15,700 people.

On Tuesday, the country recorded 41 new positive cases, bringing the total number in its outbreak to 148 – the majority of whom are Samoan, and linked to a sub-cluster who assembled at the Assembly of God church in Mangere, Auckland before the lockdown.

Jacinda Ardern said outbreak was not thought to have peaked and that country must ‘hold the course’

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New Zealand’s nationwide lockdown is extending until at least the end of the week, as the country battles to contain an outbreak of the Delta variant of Covid-19.

Auckland – the country’s largest city, where the majority of cases are – will remain in lockdown until the end of the month.

Chris Hipkins said the Delta variant was ‘like nothing we’ve dealt with so far’

The arrival of the Delta strain in New Zealand has prompted the country’s Covid-19 response minister to question the efficacy of its ambitious elimination strategy – an approach that has been the backbone of the country’s pandemic response.

Chris Hipkins told current affairs programme Q+A on Sunday that Delta raised “big questions about the long-term future of our plans”.

Jacinda Ardern has led a global Covid success story, but other countries have come unstuck when facing the Delta variant

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As epidemiologist Michael Baker scrolled through a growing list of New Zealand’s Covid-exposed locations, “my heart just sank,” he says.

Bars, nightclubs, churches, schools, restaurants and hospitals – the bullet points were an infectious disease expert’s nightmare. “Virtually every high risk, indoor environment was on that list.”