Contact tracers are urgently investigating four mystery Covid-19 cases where officials don't know how or when the person caught the virus.

Experts say the unsolved cases could keep Auckland locked down.

Genomic testing suggests two cases in one household may have got the virus from someone unknown, while two people who tested positive for Covid at Middlemore Hospital have not been linked to other cases. Cabinet is due to consider the Auckland restrictions on Monday.

On Friday, the Ministry of Health reported 11 new community cases, all in Auckland. The total number of cases in the current outbreak rose to 879, of whom 288 have recovered. There are 27 people with Covid in Auckland hospitals, four in intensive care and on ventilators.

The ministry has started reporting on the number of epidemiologically unlinked sub-clusters in the outbreak. These are groups of people who have tested positive for Covid-19 but haven't been linked to the wider outbreak. The ministry said the unlinked sub-clusters were genomically linked to the outbreak, but had yet to be linked to a known exposure event.

Seven police officers are in isolation after coming into contact with a woman who was tested for Covid at Middlemore Hospital on Thursday and returned a positive result. Thirty-six patients at the hospital were also potentially exposed to the virus after coming into contact with the woman. Staff at the hospital were wearing appropriate PPE and none had to be stood down.

Police from around the country arrived in Hamilton on Friday to help at the ten road checkpoints on the Auckland-Waikato boundary. Of the 45 reinforcements, 32 flew in on an air force C-130 Hercules.

The Government is downplaying any chance the trans-Tasman bubble could reopen soon. A Melbourne epidemiologist said the return of a full bubble would only be possible if both countries were vaccinated and accepted Covid in the community.

Vaccinated seasonal workers from Samoa, Tonga and Vanuatu will be able to travel to New Zealand without going through managed isolation and quarantine in time for the upcoming picking season, the Government says.

New Zealand's summer festival season is in doubt amid uncertainty over Covid restrictions. Tens of thousands of people are due to pack into party hot spots, but event organisers are concerned predicted tougher alert level 1 restrictions could see unworkable caps on crowd sizes.

Cafes, restaurants and bar owners around the country are anxious about the new level 2 rules, with some refusing to take on what they say is a policing role. University of Canterbury law professor John Hopkins says while businesses were required to encourage mask wearing, individuals were the ones facing prosecution if they refused to wear one without an exemption.

A Levin cafe owner says she has been the target of threats and online backlash after encouraging customers to question mandatory vaccinations and refusing to display QR codes.

A dozen Defence Force personnel are taking court action in a bid to keep their jobs despite declining to have Covid-19 vaccinations. Their lawyer, Christopher Griggs, said none of the group could be labelled 'anti vaccine”, because they'd generally had every other injection required of them.

'The applicants are standing up for their fundamental freedom to decline medical treatment without then being treated prejudicially," says Christopher.

Global toll

On Saturday morning Johns Hopkins University was showing nearly 223.6 million confirmed Covid cases worldwide, with more than 4.6 million deaths attributed to the disease, while about 5.62 billion vaccine doses have been administered.

The US has more than 40.7 million cases and 656,139 deaths, India has nearly 33.2 million cases and 442,009 deaths, and Brazil has nearly 21 million cases and 585,174 deaths.

What should I do?

Anyone who wants to get tested can find their local testing centres by visiting the Ministry of Health website.

Quarantine-free travel from Australia has been suspended.

The country outside of Auckland is at alert level 2, with masks mandatory for people over the age of 12 in more public places, such as libraries and malls.

People should use the Covid-19 tracer app.

If you are sick, call your GP before you visit, or Healthline on 0800 358 5453.

To avoid contracting and spreading the virus, wash your hands properly, cough and sneeze into the crook of your elbow and throw tissues away immediately.

To find support from people who care, connect with your community or help a neighbour in need.