Today's cases among recent returnees are from eight countries, which the ministry said was a sign of how the pandemic continued to ravage parts of the world.
"Mandatory isolation and testing will continue to be of critical importance as high numbers of New Zealanders return home before the holiday period," the ministry said.
The nine new cases:
• One person arrived from France on November 17 and tested positive around day three. They are now in the Auckland quarantine facility. • One person arrived from the Netherlands on November 17 and tested positive around day three. They are now in the Auckland quarantine facility. • One person arrived from Dubai on November 17 and tested positive around day three. They are now in the Auckland quarantine facility. • One person arrived from the United States on November 19 and tested positive around day three. They are now in quarantine in Christchurch. • One person arrived from the United Kingdom on November 14 and tested positive after routine surveillance around day seven. They are now in the Auckland quarantine facility. • Two people, who were travelling separately, arrived on the same flight from Bangladesh on November 10 and tested positive around day 12. They are now in the Auckland quarantine facility. • One person arrived from Spain on November 16 and tested positive around day three. They are now in the Auckland quarantine facility. • One person arrived from Italy on November 16 and tested positive around day three. They are now in quarantine in Christchurch.
The ministry said the latest case in the Defence Force cluster - the sixth case so far, or Case F - had been genome sequenced, confirming a direct link to the cluster.
Case F has been in isolation since November 7 and is a close contact of Case B, a Defence Force civilian worker who caught Covid-19 from Defence Force serviceman working at the Jet Park quarantine facility in Auckland.
The person is a border worker who has been isolating in a managed isolation facility for the past 10 days as a precaution, and was isolating at home before that.
They had tested negative after five days in isolation, and were tested again around day 12. A positive test was reported yesterday.
The ministry encouraged anyone who visited a location of interest during the relevant time period for the Defence Force cluster to get tested.
Two pop-up testing stations continue to operate in central and east Auckland: one on High St and one at 292A Botany Rd (Spectrum House).
"Both locations are walk-in and don't require a pre-booked appointment," the ministry said.
"We have the best chance of staying ahead of Covid-19 if everyone who becomes unwell with cold or flu-like symptoms stays at home and seeks a test quickly, and all New Zealanders are keeping track of where they've been and who they've seen."
Five other new cases were reported yesterday but they were all imported cases contained in managed isolation or quarantine facilities.
A pop-up testing location in central Auckland on High St is open this weekend, as is one in east Auckland at 292A Botany Rd (Spectrum House).
This weekend is also a significant test for automatic tracing at Beervana festival in Wellington, where people do not need to individually scan in QR codes.
Beacons will be in use and the results of the trial will help digital agency Paperkite, which is working with the Ministry of Health, to decide whether there will be any further rollout.
