Covid cases are continuing to rise across Australia, but health authorities remain confident the peak will hit before Christmas.
Cases have more than doubled in New South Wales and Victoria compared with the beginning of November, and jumped by 20% nationwide in the space of a week. The numbers build on the increases recorded last week of 10-15%.
There were an average of 14,346 daily cases recorded nationwide to 29 November, while hospitalisations increased by 19.9% to a seven day rolling average of 2,689.
But cases are climbing at a slower rate than earlier in November, when cases in NSW and Victoria were doubling in just a fortnight, driven by a “soup” of Omicron subvariants.
NSW recorded 37,796 new Covid cases in the week to 1 December, a 19% increase compared with the previous week’s 31,531.
Victoria recorded 26,971 new cases in the latest weekly reporting period, a 21% increase on the previous week’s 22,281.
No single variant is dominant in the community as the BA.2 and BA.5 sub-lineages continue to drive transmission. In NSW, 11 Omicron sub-variants and recombinant variants are circulating.
Catherine Bennett, chair in epidemiology at Deakin University, said that in the fourth wave case numbers could reflect changes in testing and reporting practices as well as underlying infection rates, making them harder to interpret.
“Sydney wastewater detections have been on the rise but patchy, with some areas showing a decline,” she said.
“Like overall infection reports, there is still an upward trend but … a tapering of growth, which is reassuring.
“I don’t think we are likely to see a sharp peak in this wave, with numbers suddenly dropping. The mix of variants that are circulating makes that less likely for us as this lifts the likelihood of reinfection.”
Deaths, which are usually a lagging indicator on cases, remain relatively stable.
NSW recorded 32 deaths in the past week, an increase of seven compared with the previous reporting period. Twelve deaths were in aged care residents, including 10 who died in a facility.
There were 1,481 people being treated in hospital with the virus, including 38 people in intensive care, as the seven-day rolling average of daily admissions decreased to 87, compared with 89 the previous week.
Health authorities said hospitalisations and ICU admissions had fallen, but the rise in Covid cases and positive PCR tests indicated “ongoing high levels of transmission in the community”.
PCR testing increased by 8.9% compared to the previous week, with the highest notification rates for people over the age of 80. About 19% of tests returned a positive result.
But rates of testing had almost halved from the beginning of the Omicron wave in winter.
The one outlier was emergency department presentations, which continued to increase week-on-week. There were 374 admissions with Covid in the latest reporting period, an increase of 53 compared with the previous week’s 321.
James Wood, an associate professor of epidemiological modelling of infectious diseases at the University of New South Wales, said he still expected cases to peak before mid-December in NSW with a “lower but broader wave” than that experienced in Singapore, a country with similar vaccination rates.
“Reported cases are still only at about the inter-wave level we saw between BA.1 and BA.2 and then between BA.2 and BA.5, so it’s still substantially lower than what we’ve seen previously,” he said.
“It’s good news that we’ve seen a decline in hospitalisations but I’m not completely sold that they have peaked yet in NSW.”
