However, nationally a fifth person has died, the third from a cluster at the Rosewood resthome in Linwood, Christchurch.
There are 15 people in hospital, with four in intensive care. One is in a critical condition in Dunedin, Bloomfield said.
He said the amount of testing has dropped off over the Easter weekend.
Bloomfield said the fifth death was a man in his 80s who had been moved from Rosewood to the Burwood Hospital.
"We need to be prepared for more possible deaths [from the Rosewood cluster]," he said.
Canterbury DHB is investigating how Covid-19 got into the rest home. The first two patients who died were a 90-year-old woman and a man in his 70s. Fears remained for other dementia patients from the home.
Prime Minister Jacinda Ardern said despite the lockdown, she hoped New Zealanders were enjoying their Easter break.
But the last couple of days should serve as a reminder why the Government implemented the lockdown.
"Our battle with this virus is far from over," she said. "Our number of cases may be small," but she said that does not show the battle is over.
She said New Zealand is not in a position to move out of level four.
"New Zealand does not take this lightly, and neither should you," she said of rule breakers caught over the weekend.
She called level three a "waiting room".
"This is a place we go while we are checking we have things genuinely under control."
On Thursday, Ardern will provide more detail about what life in level three would be like.
"We are very aware of the need to get more of our economy running," she said, in reference to the lockdown.
Week three, which starts in a couple of days, might feel the hardest.
"We're coming around the bend but can't quite see the finish line."
She praised New Zealand's lockdown efforts, but said there is more to go: "Please stay home."
• Covid19.govt.nz: The Government's official Covid-19 advisory website