Study: NZ’s shift to living with Covid-19 came with comparably lower deaths

New Zealand was the only one of four territories that managed to shift from a zero-Covid policy while keeping “excess deaths” low, a new international study finds. Photo / Alex Burton

New Zealand was the only one of four territories that managed to shift from a zero-Covid policy while keeping “excess deaths” low, a new international study finds.

In a just-published paper, Hong Kong researchers compared rates of excess mortality – or deaths above and beyond the “normal” rate in the decade before the pandemic – in New Zealand, Australia, South Korea and Singapore as each shifted to living with the virus.

While Singapore, South Korea and Australia had rises in excess mortality of 20 to 40 per cent after the transition, New Zealand’s rate stayed within 10 per cent – something the study authors partly attributed to an “ultra-high” vaccination rate among older people.

By contrast, Hong Kong recorded an excess mortality rise of more than 71 per cent over that time, largely because of very low vaccination rates among its elderly population.

Otago University epidemiologist Professor Michael Baker said the study, published in the journal Frontiers in Public Health, added to evidence that New Zealand’s Covid-19 response had been “highly effective” at minimising deaths over the pandemic.

In 2022, New Zealand recorded the largest annual increase in registered deaths since the 1918 influenza pandemic – 38,574 people died last year, 3642 or about 10 per cent more than 2021.

But it also happened to be among the few countries that had negative excess mortality over the wider pandemic period.

Had we not largely succeeded at keeping the virus at bay for the pandemic’s first two years, researchers calculated that thousands more people would have died.

A US or UK experience would have translated, per capita, to 19,900 and 13,700 Kiwi deaths respectively.

Baker said the latest study was interesting as it focused on the period when Covid-19 began spreading widely here, starting around February last year.

It also used a measure of counting extra deaths called percentage excess mortality, or PEM, as its main outcome measure, which Baker said allowed for “robust” comparisons across countries with different disease surveillance systems.

“The results of this study support New Zealand’s strong focus on reducing the health impact of Covid-19,” Baker said.

“These measures include promoting vaccination, mandatory self-isolation of cases, mask mandates in health care and aged care settings, and free access to antivirals for vulnerable groups.”

But he stressed the need not to become complacent over the ongoing impact of Covid-19, with which 2500 have died since the pandemic began.

“Despite a decline in case numbers, this virus is still on track to put more than 10,000 New Zealanders in hospital and cause more than 500 deaths this year, based on present rates.”