Covid-19: Daily cases suggest the Omicron peak is coming fast

Peak Omicron could be just weeks away now that New Zealand has recorded almost 2000 cases in a day, Covid modeling suggests.

Experts say daily cases could top 20,000, but there are too many uncertainties to know exactly what’s ahead.

friday saw 1929 new community cases across the country, bringing the active total to 9874. Seventy-three of those were in hospital, and all regions except the West Coast now have cases. There have been no deaths in the latest outbreak.

Recent modeling done by a group Kiwi academics indicated infection and hospitalization rates depended heavily on how many people get booster shots.

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They estimated an outbreak could be as short as 100 days, if following the New York pattern, or nearly twice as long if similar to South Australia. It is four weeks since New Zealand’s first community Omicron case was detected.

The modeling also suggested that people hunkering down out of circulation and re-emerging later could lengthen the outbreak’s tail, or trigger a second wave.

One of the report’s modellers, Professor Shaun Hendy, said the outbreak was on track to follow overseas examples such as some Australian states.

The trajectory of the spread indicated a mid-March or late-March peak, with cases coming down in April, he said.

He warned while case numbers will drop off, the variant will not be stamped out.

“But even if we have a short and rapid decline, we will still be dealing with this in June and July. This is not going to just hit us and go away.”

New Zealand’s high vaccination and booster rates could “start to bring the peak down earlier” than Australia’s, he said. Conversely, while Omicron hit Australia over summer, it would affect New Zealand over cooler months when respiratory viruses spread quickly indoors, he said.

“It may look a bit different here. Overseas you saw a sharp decrease as cases came down rapidly. I think we are going to see a more complex pattern.

“If we are more cautious, we will bring the peak down, but spread the outbreak out. If we flatten it we could maybe push that peak into April.”

Hendy said because the vaccine’s protection waned after three or four months, “in some ways, now is the ideal time to have this outbreak”.

Covid modeler Rodney Jones said while the “broad outline” of an Omicron outbreak was understood, there were too few specifics available to model is accurately.

He said that unlike Delta, Omicron was “super fast, more like a flu, and people often don’t know they’ve got it”.

Jones compared New Zealand with Queensland, which has a population of 5.2 million, spaced out with one large city, and where Delta was eliminated inside closed borders.

Queensland’s outbreak began in late December, peaking in late January later with about 20,000 infections a day, and is now recording about 5000 a day. From 500,000 cases the state has suffered about 450 deaths, and has a vaccination rate not quite as high as New Zealand’s.

“Omicron spreads like wildfire. It’s really a different disease, and we are incredible well-vaccinated, one of the best vaccinated countries in the world,” Jones said.

“That will stand us in good stead.”

Professor Peter McIntyre from Otago University, a paediatrician and infectious disease specialist, said the amount of public mingling and preventative measures like mask wearing would help determine the length of the outbreak.

”If you flatten the curve, you probably also lengthen it and we’ll have it for longer. It won’t be short and sharp like London and New York. It’s a bit of a trade-off.”

McIntyre said that while the vaccine’s ongoing protection again infection would wane as the weeks go on, its defense against severe illness and death would last longer.

“What we are expecting to achieve from the vaccine is individual protection, not stopping it in its tracks. Omicron is a different disease.”

Rod Jackson, professor of epidemiology at Otago University, said “no-one knows” how long the outbreak will last.

“Covid does not follow a time frame. People cry out for certainty. But you can’t have certainty with a virus.”

Jackson said flattening the curve was essential to reduce hospitalizations and deaths and keep businesses functioning.

“It’s just a numbers game. On average, Omicron is not severe. If you’re vaccinated, it is relatively mild.

“But we can’t just let it rip, but the downside is a longer period of ongoing restrictions. We have to be cautious and flexible. We’ll have to be ready to respond as it plays out.”

McIntyre was less cautious about letting the virus move through the community.

“I am at the optimistic end. I think without Delta and with vaccination, it is probably not going to be too bad. Not as bad as some of the scenarios.

“If you are under 40 and you don’t have significant health conditions, getting Omicron after a booster is probably the way to go.”

He said New Zealand’s main focus must be vaccination.

Analysis of recent New Zealand cases reveal unvaccinated people are 27 times more likely to be hospitalized than those who are fully vaccinated and boosted.

“The unvaccinated, or under-vaccinated, are the people that will be welcomed into ICU. It’s crucial to help stop people clogging up hospitals, and affecting our usual health services,” McIntyre said.

“With the borders opening, it’s no longer going to be about the number of cases, it’s going to be who the cases are.”

McIntyre said most people will not “be hit for six” if they catch Omicron. Protecting the frail and vulnerable would require a combination of shielding, rapid testing and anti-virals, he said.

“We are all moving from the successful elimination phase. We had a psychology of search and destroy. This is a big psychological shift. We have to pivot our thinking.”