Concern about how quickly Delta could spread around the country. 

Cases have been reported in Karāpiro and Kāwhia - well south of the Level Three border -- and a weak positive has been reported in Whangārei. 

One mayor is now calling for the entire upper North Island to be put back in Level Three -- while Wellington Mayor Andy Foster says it's only a matter of time until Covid spreads much further south. 

Auckland University epidemiologist Rod Jackson told Mike Yardley the Delta variant is proving very difficult to control. 

"Delta is like a human flamethrower in a forest; if you're vaccinated you're like a clean, green pine tree. If you're unvaccinated you're like an Aussie gumtree." 

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