New Zealand appears to have dodged an “exponential” rise in coronavirus cases, the country’s director-general of health has said, saying he feels “encouraged” that strict, nationwide lockdown measures are beginning to take effect.

New Zealand’s 5 million people have been in total lockdown for nearly two weeks, with no-one allowed to leave their home unless fetching essential supplies, or taking exercise.

With a record number of tests conducted on Sunday, director-general of health, Dr Ashley Bloomfield, said the number of cases had begun to stabilise, with 39 new confirmed cases and 28 new probable cases, bringing the total to 1106.

A total of 13 people were being treated for the illness in hospital, Bloomfield said, including three in intensive care units, with one of those in a critical condition. So far one person has died from the virus in New Zealand, a woman in her 70s with underlying health conditions on the west coast.

Bloomfield said he was cautiously optimistic that it appeared coronavirus cases were beginning to flatten out, and it appeared the government’s swift move from level two to four in the space of two days seemed to be working in containing the virus, and stopping widespread community outbreak.

“So some success so far, but our aim is to stamp it out,” Dr Bloomfield said.

The cautious optimism came as the prime minister, Jacinda Ardern, said she would not rule out her and her ministers taking a pay cut to ensure they played their part in getting the country and the economy back on its feet.

“I know my colleagues well and I know we are all acutely aware of the pain our communities are feeling, so you can imagine the kinds of discussions we’ve been having – I won’t rule it out,” Ardern said of a potential cut. Ardern makes more than NZ$400,000 a year, while her ministers make more than NZ$200,000.

‘I haven’t given any specificity on numbers or reach, but I won’t rule it out, I think I know pretty well the people I work with.”

Ardern said she was quietly pleased with the progress New Zealand was making with containing the virus, but quashed mounting speculation that the country may move out of total lockdown early. Ardern said the fastest way for Kiwis to get out of lockdown was by adhering to the rules of it and waiting it out.

“We have positive signs, not least the fact that we could have had 4,000 cases now, instead of 1,000,” Ardern said.

“But I don’t want to get ahead of ourselves … though the signs are positive.”

Regions of the country with a high number of cases – including Auckland and the deep south – may remain in lockdown longer, Ardern said, and all regions of New Zealand should be prepared for moving in and out of the different alert levels, depending on their situation, after the month-long lockdown ends.