Border workers face fines of $1000 if they refuse weekly or fortnightly Covid tests, as the Ministry of Health announced five new cases on Sunday - four community cases linked to the Mt Roskill church cluster and one in managed isolation.
But international aircrew or aircrew based in New Zealand will be exempt, with airlines imposing their own testing regimes.
The regular testing of border-facing workers was something the Government had trumpeted as part of its testing strategy at the end of June, but the ministry's testing strategy was completely at odds and most of those workers hadn't been tested at all.
The thousands of border-facing workers, including those at maritime ports, were to be tested twice to see if there were any clues about the origins of the current outbreak. So far no one has tested positive, and the second round was hoped to be completed by the end of Sunday.
The new law came into effect at midnight last night to ensure those workers are tested regularly. If they refuse a weekly or fortnightly test, for no good reason, they can be fined $300 by an enforcement officer or up to $1000 by a court.
Four of the new cases announced on Sunday were community cases and one is a traveller who is in managed isolation.
The four community cases are all linked to the Mt Roskill Evangelical Church group in Auckland.
They are all females, one aged 5-9, two aged 20-29 and one aged 60-69.
The one imported case is a man in his 20s who arrived from India on August 23 and who has been staying in an Auckland isolation facility. He is a close contact of an existing confirmed case and tested positive following routine testing around day 12 of his stay. He is now in quarantine.
The Christchurch case that was under investigation at the weekend has now been confirmed as not a case of Covid-19. "The investigation has been closed," the ministry said.
The Ministry of Health announced in a 1pm press statement on Sunday that the Government had passed a new Public Health Response order to require border-facing workers to be regularly tested. It came into effect from midnight last night.
The new order puts into place the regular testing of workers going forward.
Workers refusing a test without a reasonable excuse can be fined up to $1000.
Starting this week, workers at a quarantine facility will be tested once a week, as will workers who transport overseas arrivals to and from such a facility.
Workers at a managed isolation facility and those driving returnees to and from such facilities will be tested once a fortnight.
Government border-facing workers including immigration, customs, primary industries and aviation security officials will be tested once a fortnight, as will DHB workers and retail and food and beverage workers at the airport.
Airport workers handling international baggage trolleys, airport cleaners and airline workers who interact with passengers will also be tested once a fortnight.
Port workers will also have to be tested once a fortnight, including pilots and port workers who work on or around ships, and people who transport others to or from ships.
Some people will qualify to be exempt from testing for medical reasons.
Airline workers who don't interact with international arrivals will not have to be tested.
There were 7178 tests yesterday.
Of 3217 close contacts identified with the current outbreak, only 30 are still to be reached.
There are 75 people linked to the community cluster who remain at the Auckland quarantine facility, which includes 58 people who have tested positive for Covid-19.
There are four people in hospital; two are in North Shore Hospital's general ward, one is in a general ward at Middlemore Hospital and one is in ICU in Waikato Hospital.
The total number of active cases is 116. Of those, 39 are imported cases in MIQ facilities, and 77 are community cases.
Auckland is at alert level 2.5 while the rest of the country is at level 2 until 11.59pm on September 16, even though all the current cases are in Auckland or are linked to the 155-person Auckland cluster.
Part of the Government's rationale for keeping the rest of the country at level 2 is to provide some protections - physical distancing and a 100-person limit on gatherings - while people are allowed to travel in and out of Auckland.
Prime Minister Jacinda Ardern said that was evident with the recent cases in Tokoroa, where potential spread of the virus could have been worse if that part of the country had been at alert level 1.
On Saturday there were two new cases in the community, both epidemiologicaly linked to the Auckland cluster.
"One case has been linked as a close contact to the Americold household sub-cluster and the other is a close contact of a confirmed case linked to the Mt Roskill Evangelical Church sub-cluster," the ministry said.
The Covid-19 death toll reached 24 on Friday, with the death of a man in his 50s and that of 85-year-old former Cook Islands prime minister Dr Joe Williams.
The deaths were a "stark and sad reminder of just how deadly this virus is and can be", Ardern said.
Williams' death at Auckland City Hospital marked a double tragedy for his family, after the respected Mt Wellington GP's brother Tuaine Williams, 92, died peacefully a day earlier at The Prince Charles Hospital in Brisbane.
Williams was a former Cook Islands health minister who later led the country for four months in 1999. He was also a New Zealand First candidate in 2005 and yesterday received tributes from Deputy Prime Minister Winston Peters as well as director general of health Dr Ashley Bloomfield and Finance Minister Grant Robertson.
Williams was admitted to hospital on August 13 and was thought to have come in close contact with someone connected to the Auckland August cluster.
That cluster, which sparked Auckland's almost three-week return to level 3 lockdown, was first detected on August 11 in a family member of a worker at Americold coolstore, which is near Williams' Mt Wellington practice.