New Zealand has extended its strict lockdown again as it tackles a Delta outbreak causing 70 new cases a day

• New Zealand has extended its strict lockdown by another four days as Delta continues to spread.
• The country locked down on August 17 after it detected a single case that officials assumed was Delta.
• Now, an outbreak has caused 347 cases.

New Zealand has extended its strict lockdown for a second time to try to stamp out the highly infectious Delta variant.

The country locked down on August 17 after it detected a single case of COVID-19, which officials assumed was caused by the Delta variant.

Officials had already extended the lockdown by an extra four days on Monday - and on Friday, Prime Minister Jacinda Ardern said in a briefing that lockdown would last for another four days, until August 31, for most of the country.

Auckland, New Zealand's largest city and the epicenter of the outbreak, will "likely" be under the nation's strictest level of lockdown, Level 4, for at least another two weeks, health officials said.

"Our most effective tool is Level 4," Ardern said.

Since the start of this outbreak, New Zealand has recorded 347 cases - 333 of these were in Auckland.

It has recorded a total of 3,228 cases and 26 deaths since the pandemic begun, according to Johns Hopkins University.

On Friday, the country recorded 70 new infections, all in Auckland, official data showed, which was up slightly from 68 new daily cases on Thursday.

Ardern said that the number of cases may be beginning to "plateau."

"Our job is to keep up the hard work in order to bend and then flatten that curve," she said.

"We have evidence that what we are doing is working, but caution is still required," she said.

Ardern said that 19 people in New Zealand with COVID-19 were in hospital. One person was in a "stable condition" in ICU, she said.

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Ardern said in a briefing Wednesday that the country would stick to its "elimination" strategy to tackle the Delta variant, which has mutations that help it avoid the immune response.

"Elimination means continuing to stamp out COVID where ever it emerges," she said, adding that the country wanted to get people vaccinated to provide their own "individual armour."

"For now, while we vaccinate, elimination is the goal and we can do it," she said.

The country has ramped up its vaccine drive, giving a COVID-19 shot to just under 2% of the population in a single day on Friday - the most of any day during the pandemic, officials said.

So far, New Zealand has fully vaccinated 21.3% of its population, according to Johns Hopkins University. The world average is about 25%, according to Oxford University's Our World in Data.