Worst of Covid over, experts say

Australia has now seen the worst of the Covid-19 pandemic and future waves of infections are likely to be smaller with less severe disease.

Infectious diseases physician and Australian National University professor Peter Collignon says people were still strongly advised to get boosters.

Australia has now seen the worst of the Covid-19 pandemic and ­future waves of infections are likely to be smaller with less severe disease, top infectious disease modellers say.

Evidence is emerging globally and in Australia that the widespread combination of vaccines and natural infection is likely to lessen the impact of future waves, as cases and hospitalisations from the Omicron BA.5 outbreak drop across the nation.

New Covid-19 infections on Tuesday dropped by nearly 10,000 in the space of a week from 35,659 new infections last week to 26,746 this week – and Covid-­related hospitalisations have also fallen by nearly 5000 cases.

James Wood, a leading modeller for the NSW government, told The Australian on Tuesday it was unlikely Australia would see another epidemic wave this year. “I think the most likely situation is another variant will branch off Omicron,” Professor Wood said.

“There might be another Omicron-like leap, but if that doesn’t happen, we can expect the viruses to branch off from Omicron, and then we would expect hybrid immunity to be relevant, so we’d expect to see smaller waves and less overall health impacts on the population. If we don’t see an ­Omicron-like jump, this is as bad as it’s going to get.”

Victorian infectious diseases modeller Romain Ragonnet backed that assessment.

“The only thing we need to consider is that the main driver of resurgence is the emergence of new variants, and this we can’t predict,” Dr Ragonnet said.

“But I would think that if no major variants emerge in the ­future or if the variants remain similar, I am really optimistic about the future waves. They should be smaller. There should be less hospitalisations because the population will have more ­immunity. Eventually it will settle down and end up being seasonal like flu.”

It had been feared that the ability of new variant and subvariants to evade vaccine immunity might drive ongoing epidemic large waves of the virus.

But newly emerging evidence about the strong immunity conferred by vaccination plus natural infection is easing those fears and instilling confidence among infectious diseases experts that protection from severe disease is robust and relatively long-lasting.

The Australian Technical Advisory Group on Immunisation has said people who have had a confirmed case of Covid-19 plus vaccination should feel reassured that the hybrid immunity conferred “appears to produce strong and durable protection against ­future infections, and severe disease and death”.

Infectious diseases physician and Australian National University professor Peter Collignon said people were still strongly advised to get boosters. “As more people eventually get infected, they get mucosal immunity and therefore there’s less spread,” he said.

Professor Collignon said he now believed the Covid-19 pandemic “will probably follow the same course as the Spanish flu did” in being very severe for two to three years and then result in ongoing lower-grade spread for decades. “My guess is we’ve seen it as bad as it’s going to get with Covid this winter,” he said. “I do think the worst is over.”

 

University of Melbourne epidemiologist Tony Blakely was cautiously optimistic that future waves would be less severe in terms of hospitalisations and deaths provided future variants were similar to BA.4 and BA.5, but he said “we have a long way to go with this pandemic”.

“There remains the possibility, a chance that is impossible to predict, that a new variant comes along that is non-Omicron like and has both higher infectivity and virulence.”

Federal Health Minister Mark Butler said the government was preparing for future Covid-19 waves. “The CMO has said this third wave of Omicron will not be the last wave of Covid-19 Australia faces,” he said.

“It is not possible to predict the scale and severity of future waves, but Australians can … do some simple, easy things to protect themselves and others.

“This includes staying up to date with vaccinations.”