New Zealand's outbreak of COVID-19 cases caused by the more contagious Delta variant has surpassed 100 on Monday, prompting officials to extend a new wave of lockdowns.

Prime Minister Jacinda Ardern on Monday announced an extension to the country's strict nationwide COVID-19 lockdown amid the spread of the Delta virus. During a news conference, the prime minister also warned against more cases, noting that the new wave of cases has yet to peak.

New Zealand's COVID Outbreak

"The safest option for all of us right now is to hold the course for longer," Ardern said at a news conference, according to Reuters. "If the world has taught us anything it is to be cautious with this variant of COVID-19."

The cluster of cases began last Tuesday after New Zealand officials detected the first community case in nearly six months in a 58-year-old man from Auckland. The total number of confirmed infections has now grown to 107 cases, with 35 more people testing positive on Monday.

New Zealand health officials are now investigating more than 320 locations of interest linked to the people who tested positive for COVID-19, including bars, nightclubs and churches. More than 13,000 contacts are also being investigated by officials.

"My heart just sank. Virtually every high risk, indoor environment was on that list," Michael Baker, an epidemiologist, told The Guardian.

The lockdown would remain until midnight Friday for provinces outside of Auckland while the epicenter of the outbreak would remain on the highest level of lockdown until Aug. 31.

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New Zealand previously adopted a "Covid zero" elimination strategy, which has helped the nation reduce its COVID-19 deaths to 26 throughout the pandemic. However, this strategy was questioned by Chris Hipkins, the country's COVID-19 response minister, who worries that the strategy may not be viable against the more transmissible Delta variant.

Stomping Out the Infection

"Our plan has worked before and together we can make it work again," Ardern defended, according to Yahoo News.

The prime minister added that they plan to relax all coronavirus-related restrictions next year when the country's vaccination rates are higher. As of Monday, only 20% of the country's total population have been fully vaccinated against the virus.

Shain Hendy, a scientist who heads the Te Punaha Matatini research center in New Zealand, said they are expecting to see a decline in COVID-19 cases towards the end of the week, according to Axios.

The outbreak comes as the Delta variant virus outbreak in Sydney threatens to go out of control, with health officials reporting more than 600 new infections consecutively in the last four days. The outbreak in Sydney is also said to be the origin of the outbreak in New Zealand.

Officials in Sydney have now extended their lockdown through September on Friday. Tougher COVID-19 restrictions were also announced, including a curfew and mandatory wearing of face masks.

Sydney has been placed in lockdown since June 26, which came nearly two weeks after an unvaccinated limousine driver tested positive for the Delta variant, according to ABC News.

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