The plan for people with Covid-19 to isolate at home suggests the government believes the spread is wider than had been thought, epidemiologist Rod Jackson says.
Covid-19 Response Minister Chris Hipkins said home quarantine would be introduced "fairly soon" as a necessary step to prevent MIQ spaces being limited even further for people coming to New Zealand from overseas.
University of Auckland professor of epidemiology Rod Jackson said the outbreak had to be slowed down.
"Last night, there were 75 unlinked cases in Auckland. What that means is there's a lot more cases out there."
He said the speed of the spread of Delta variant makes this outbreak worse than any previous one.
"I think the government's clearly signalling that MIQ is going to be overwhelmed, the next thing is hospitals are going to be overwhelmed, everything's going to be overwhelmed.
"We've just got to got to slow it down as much as we can."
There were "huge risks" involved with home isolation, he said, "but to me, it suggests that ... they believe this problem is much much wider than we thought".
"We are in a race against time to get everyone vaccinated, we just have to use everything in our power to slow [the outbreak] down as much as possible."
Jackson said returning to a period of level 4 lockdown may have little effect on the growth of cases.
"Covid is spreading among a group of people who are breaking the rules.
"You can be really hard on them, but you're probably not going to ever stop them."
Jackson said vaccination should be mandatory for more sectors.
"I think it has to be the police, it has to be supermarkets. The other thing is that businesses are crying out for the license to introduce their own mandates."
With more than 80 percent of eligible New Zealanders having had at least one vaccine dose he said "the tide was turning" against those who were not vaccinated.