Omicron measures must stay, say experts

Experts have compared Australia’s Omicron experience with our own to conclude New Zealand needs to strengthen its public health measures rather than relax them.

Kiwis learn today whether the country will shift to the orange traffic light setting, which would remove capacity limits but still require masks to be worn at many indoor venues.

Ahead of that decision, Otago University public health experts Dr Jennifer Summers and professors Michael Baker and Nick Wilson have published a commentary calling for urgent and widespread improvements to our pandemic response — namely with higher vaccination coverage and strong mask measures.

As for what New Zealand might expect on the other side of our Omicron peak, the researchers looked across the Tasman.

Omicron took root in Australia about a month and a half earlier than here. But the wave of infections and hospitalisations was much larger than either had seen before.

Protections need to be strengthened.

Dr Jennifer Summers

“When we observed the first Omicron wave in Australia in January, we had a reasonable idea of what New Zealand could expect in terms of case-load and what this could mean for the health system,” Summers said. “What we see now is that Australia had a higher hospitalisation rate per 100,000 population at its peak of the first Omicron wave compared to New Zealand.”

However, when the researchers broke out Auckland’s Omicron wave, which peaked ahead of the rest of New Zealand, that regional ratio proved much higher, with the city’s seven-day case average peaking at about 637 per 100,000 in early March.

Australia’s mid-January peak reached a seven-day case average of about 423 per 100,000, while a lateMarch peak in the rest of New Zealand hit a high of about 410.

Looking at hospitalisation rates, peak numbers of patients with Covid in Australia reached nearly 5400 in late January — and a similar lag was observed in Auckland, with a peak of more than 630 in mid-March. Auckland’s hospitalisation rate per 100,000 was much higher than Australia’s and the rest of New Zealand’s.

On January 21, Australia recorded a peak-high of 424 intensive care unit (ICU) beds occupied, compared with 33 in New Zealand on March 21.

While Australia now appeared to have a second wave, the researchers pointed to the impact of the fasterspreading BA.2 sub-variant. Because BA.2 arrived here soon after the original BA.1 subtype, New Zealand has effectively seen two Omicron outbreaks at once.

Although that could mean another flare-up here might prove smaller compared with other countries, Summers pointed to the danger of subsequent waves after that.

“To prepare for this likely scenario, public health protections need to be strengthened in New Zealand, not lessened,” she said.

That included lifting vaccination rates across all age groups, and offering a fourth dose to the vulnerable, reducing the minimum age for boosters to 16.

More broadly, we needed to beef up Covid surveillance and upgrade our protection framework to be adaptable to new variants.