New Zealand's first batch of Pfizer-BioNTech coronavirus disease (COVID-19) vaccines is unloaded from a plane after arriving in Auckland, New Zealand, Feb. 15, 2021.
New Zealand's first batch of Pfizer-BioNTech coronavirus disease (COVID-19) vaccines is unloaded from a plane after arriving in Auckland, New Zealand, Feb. 15, 2021.

Officials in New Zealand Monday were tracing the sources of three coronavirus cases that sent the nation’s largest city into its first lockdown in six months, on the same day the first doses of vaccine arrived in the country. 

Prime Minister Jacinda Ardern implemented a 72-hour lockdown Sunday for Auckland’s nearly 2 million residents after the cases were discovered, closing schools and non-essential businesses. 

Officials say the new cases involve members of one family.  Health Ministry officials said genomic testing confirmed two of the cases were determined to be the variant which was first discovered in Britain and has been found to be more easily transmissible. 

But as of Monday, the health officials said there were no other positive cases detected so far beyond the initial cluster.

At a news conference Monday, Health Director-General Ashley Bloomfield said the negative test results since the first three were found was an encouraging start but cautioned a fuller picture of the outbreak wouldn’t emerge until Tuesday, when the results from expanded testing would be known.

Meanwhile, Ardern also confirmed the arrival of shipment of about 60,000 doses – 30,000 full courses - of the Pfizer and BioNTech vaccine. She said once safety checks are completed, vaccinations should begin Saturday, with border workers the top priority.

The Auckland shutdown is seen as a setback for New Zealand, which has received praise worldwide for its success against the virus that causes the COVID-19 disease. The nation of 5 million has seen just 25 deaths from the disease, according to the Johns Hopkins University, which is tracking cases globally.