Health workers and testing labs have been under increasing pressure as the Omicron outbreak grows, and have been hoping for a swift shift to the next phase of the Government's plan.
What is phase three?
Phase three is designed to help the health system handle an Omicron outbreak of several thousand new cases a day.
The shift means a greater focus on individual responsibility, rather than relying on health services to be able to cope and contact trace in the way they had earlier in the pandemic.
Testing
Rapid antigen (RAT) tests will be considered enough to diagnose symptomatic people and priority groups.
These tests, which are self-administered and give results in 15 minutes, should be available from doctors, pharmacies, community testing centres or workplaces.
Critical workers including those in healthcare can use these tests daily to be able to go to work even if they are a close contact, so long as their employer is signed up to the scheme.
Cases should get a test on day three and day eight of their isolation period, as should household contacts. Contacts not living in the same house should get a test on day five or if symptoms appear.
PCR testing will continue to be used for those who need it.
Case and contact management
People testing positive are notified by text message, not a phone call, and will be sent a link to complete an online contact tracing form. There will be a phone call option available for those without internet access.
Contacts may be automatically notified from the contact tracing form, but cases can also be expected to notify their close contacts themselves.
The definition of 'contact' changes to mean household and household-like contacts only. Contacts will only be required to isolate if they are high-risk (household) contacts.
Notification of locations of interest are restricted to the most high-risk events.
Isolation
Isolation times remain the same as the shorter period introduced in phase two: 10 days for cases, seven days for contacts.
However, household close contacts should continue to isolate until the case in their home has completed 10 days isolation.
Most people who test positive will be expected to look after themselves at home, leaving clinical care available for those with greater need.
Official messaging is that there is unlikely to be other accommodation - such as MIQ - available for most cases. However, the Government has repeatedly said arrangements will be made for those who have no home, are living in a vehicle, or are in other difficult circumstances.
Why do we need it?
While Omicron is considered milder than the dangerous Delta variant and is less likely to put people in hospital, some people do still get very sick and it spreads so quickly many more people can be expected to get very ill.
That is, while any one person is less likely to get severe symptoms, many more people overall can be quickly expected to get the virus, so the total number of people who do end up in hospital all at once is likely to be significant.
New Zealand has been recording steadily increasing numbers of daily cases, topping 3000 yesterday, and Prime Minister Jacinda Ardern has this week been saying the outbreak is not expected to peak for three to six weeks, and the nature of Omicron means case numbers can be expected to keep doubling every three to five days until we near that peak.
Ardern signalled New Zealand was likely to move to phase three when the country was hitting about 5000 daily cases. The Government had said it was possible we might never reach that scenario but it now seems inevitable, and with high test positivity rates impacting laboratories' ability to process PCR tests at the rate required, it makes some sense to be moving early.
New modelling shows the peak of Covid-19 in the Omicron outbreak in Auckland and Northland alone could reach 4000 daily cases, if transmission is low, or 9000 if it is not.
Even a low-transmission scenario would mean about 400 cases from Auckland and Northland in hospitals at any given time. It would put heavy strain on New Zealand's health system - general wards as well as intensive care - which has suffered decades of underinvestment from successive governments.
The high number of cases means the follow-up interviews with cases and high-intensity contact tracing systems will not be able to keep up, so the systems will instead focus on the most high-risk people.
During this time, New Zealand can also be expected to remain in the red traffic light setting. Ardern has suggested these settings, the vaccine passes and mandates are likely to last until the country has progressed well past the peak of cases, so the health system remains operational.
Vaccinations - especially booster doses - are a big help in reducing hospitalisation from Omicron, and New Zealand's high rates will have helped prevent some of the high death rates seen overseas.
Masks and other public health measures like frequent, thorough hand-washing also help slow the spread of the virus, so it will be important for people to continue to do this while the virus is spreading.
While the Government says it intends for heavy lockdowns to be a thing of the past, the traffic light system does maintain localised lockdowns as an option should things get really out of control.
Meanwhile, the Government is also gearing up for more people to start isolating at home when arriving from overseas, beginning from next week with those coming from Australia and expanding to New Zealanders coming from the rest of the world two weeks later.
