Covid-19 is on track to kill some 1000 people this year and cause 10,000 hospitalisations, Professor Michael Baker says – underscoring the need for caution in easing our few remaining protections.

The Otago University epidemiologist argues that Cabinet – soon due to again review Covid-19 settings – should be “reluctant” about following other countries and scrapping the mandatory isolation period for cases.

While case and hospitalisation rates were running much lower than during last year’s dramatic surges – reflecting widespread population immunity built up from vaccination and infection – Baker said the coronavirus was continuing to prove a heavy burden.

“It’s our number one infectious disease killer, and the number one infectious disease that’s placing people in hospital.”

Over the most reporting week, the Ministry of Health recorded another 275 hospitalisations and 16 deaths, bringing New Zealand’s cumulative toll to 2687.

With more than 300 deaths already reported in 2023, Baker expected Covid-19 to claim twice as many lives this year as those typically attributed to influenza, which averages about 500.

One new Israeli study indicated that adult patients with Omicron – a variant considered less severe than earlier types like Delta – had a higher death rate than those hospitalised with seasonal flu.

It found those patients were about 55 per cent less likely to die within 30 days than those hospitalised with Omicron, as observed over Israel’s 2021-22 flu season.

New Zealand’s Covid-19 deaths have predominantly occurred among older people, with Māori, Pasifika people and those living in deprivation featuring disproportionately in mortality data.

Long Covid remained another ongoing threat – one recent study suggested as many as one in five Kiwis reported lingering symptoms after their first infection – but vaccination appeared to greatly help in reducing risk, as it did with severe infection and death.

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“Things may be less intense right now, and Covid-19 has obviously been displaced from the headlines by other news items, but we need to retain a lot of respect for this virus and the damage that it can do.”

“It’s our number one infectious disease killer, and the number one infectious disease that’s placing people in hospital," Otago University epidemiologist Professor Michael Baker says. Photo / Supplied

Within weeks, Cabinet is due to decide whether to keep our few remaining measures, which include the mandatory requirement for cases to self-isolate for seven days, and mask use in some care settings.

While many countries have retained masking orders in certain instances, few have self-isolation requirements still in place: the UK ditched its last February, with Australia following in August.

Covid-19 modeller Dr Dion O’Neale said it was difficult to calculate precisely what impact dropping measures here would have on virus spread.

While his team observed an increase in transmission following last spring’s major rollbacks, only half of that rise was attributed to requirements like widespread masking actually stopping.

The rest of it could likely be explained by behavioural changes that those rollbacks influenced, with some Kiwis perhaps taking them as a cue not to test or self-isolate anymore.

O’Neale added that easing isolation rules would be best done at times when case numbers were lower.

“For instance, a 10 per cent increase in transmission when we’ve got 1000 cases a day gives you a much smaller increase than when we’ve got 5000 a day.”

In any case, Baker said the Government would need to weigh its own decision carefully.

“I think we need to consider the massive strain Covid-19 is having on the health system, which is one of the reasons why New Zealand introduced these requirements in the first place,” he said.

“Governments have every right to say, our health system is under stress and therefore we’d require people not to add to it with avoidable diseases – it’s pretty reasonable.

“I hope that most New Zealanders understand the personal and societal benefits about sticking with these kinds of requirements.”

The Government has already tweaked mask requirements in healthcare: but visitors are still required to wear them, as are clinicians in cases like treating patients with symptoms of acute respiratory virus infection.

That came as another new paper, just presented by researchers at UK’s St George’s University Hospital, suggested hospital-wide mask restrictions might not be making much of a different to rates of spread in the Omicron era.

“Any measures taken need to be appropriate and proportionate," Health Minister Dr Ayesha Verrall says of Covid-19 settings. Photo / Jed Bradley

Health Minister Ayesha Verrall said the review was being informed by advice from public health officials, along with the Government’s Covid-19 Technical Advisory Group.

“The assessments always consider the risk to the community, current case and hospitalisation numbers, the current capacity of the health sector and the latest national and international data and evidence,” she told the Herald.

“Any measures taken need to be appropriate and proportionate.”

If not ultimately mandated, Baker said staying home when sick to prevent spread at least needed to become more of a “cultural norm” in New Zealand.

More broadly, Baker and colleagues have sounded a critical need for the Government to find a better strategy to tackle all respiratory illnesses - including improved ventilation in public buildings, targeted and universal vaccine programmes and smarter mask use.

“We also need to get much better at doing comprehensive, integrated surveillance of respiratory viruses, which are almost certainly where future pandemics will arise from.”

In the meantime, he urged those eligible to book their Covid-19 and flu vaccinations ahead of the winter season, which may also bring the return of two influenza strains that New Zealand’s seen little of since 2019.

“I’d say all bets are off as to what we’ll see this flu season.”