We could be waiting a little bit longer to know if the short, sharp lockdown is bringing the Covid-19 outbreak under control. 

New Zealand now has at least 148 cases in the community. 

The Ministry of Health has also identified more than 15,000 contacts and more than 450 visits to almost 350 locations of interest, with Farmers Westfield Albany being added to the list this morning. 

Canterbury University Covid modeller Michael Plank told Mike Hosking more contacts will be identified, but it will take time. 

"We do have to be patient, I'm sure those contact tracing teams are working as hard as they can to find those contacts, get them in and get them tested." 

Meanwhile, Otago University's Michael Baker says he's concerned that a staff member at Middlemore Hospital's Emergency Department has tested positive for Covid-19. 

However, health officials say the risk to the public remains low as the person is fully vaccinated, and showing no symptoms. 

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