'Optimal' policy settings for any new wave include targeted vaccinations for the over-30s, plus masks and distancing.
The government must introduce more stringent public health measures, such as physical distancing, to protect Australians should there be a new covid wave driven by a particularly infectious variant, according to new research.
The recommendation comes in a paper, published today in The Lancet Regional Health – Western Pacific Journal, which sought to identify optimal policy settings for the 12 months from October 2022. The study’s researchers, based at Melbourne University, modelled what would happen based on a range of permutations for vaccination, mask wearing and public health measures.
Policies were ranked based on four evenly weighted criteria: cost-effectiveness from (a) the health system only and (b) the health system plus GDP perspectives, (c) deaths and (d) days exceeding hospital occupancy thresholds.
While the study only examined what could be done in Victoria, the recommendations could be applied to the whole of Australia, said Professor Adrian Esterman, a former adviser to the WHO and a currentprofessor of biostatistics and epidemiology at the University of South Australia, who was not involved in the study.
According to the study, optimal policy in the coming year would comprise “more stringent public health and social measures (PHSMs), two further vaccine doses (an Omicron-targeted vaccine followed by a multivalent vaccine) for over-30-year-olds with high uptake, and promotion of increased mask wearing (but not government provision of respirators)”.
However, the research predicted high numbers of infections and deaths in Victoria during the 12-month period across all future variant scenarios, with 4.2 million infections and 8100 deaths on average, regardless of the policy implemented.
The paper also noted there would be an unavoidable economic cost.
Professor Esterman said he was unsurprised by the conclusions the researchers had reached, noting that the government needed to do more in the area of public health measures.
“We’ve known for ages that the best approach is the ‘vaccine-plus policy’, where you get people vaccinated as much as possible and you have some public health measures in place – and that’s what we’re not doing now,” he told TMR.
“One of the things that came out of the research was that it’s better to vaccinate the over-30s rather than the over-60s, and at the moment, the sort of bivalent vaccine that’s available is only available for people in the older age group.
“This is an ATAGI recommendation, but the government can’t do anything about ATAGI’s recommendations. ATAGI are due to pronounce in the next few weeks whether to open up the bivalent vaccine to a much broader group of people, but it will still probably be the over-60s,” he said.
“One of the problems with vaccinating the much younger people, especially men, is that the balance between the risk of being vaccinated and the risk of covid isn’t quite so clear, because younger people – men in particular – tend to be [susceptible to] myocarditis and pericarditis from the vaccine,” he said.
While the researchers considered 104 different scenarios, the possible emergence of SARS-CoV-2 variants of concern and any associated changes in viral transmissibility, immune escape capacity (which has, in the case of the Omicron variant, greatly reduced protection following vaccination and prior infection) or virulence were not modelled.
As of 12 January, the Omicron XBB.1.5 variant and its sub-lineages were considered a variant of “interest” in Europe, but not one of “concern”.
An important measure in coming months will be to slow rates of infection, according to Professor Esterman.
“What the government should be doing but isn’t doing is having some brakes on infection through some minor public health measures and they’re simply not doing that,” he said. “But if we get this much more infectious sub-variant XBB.1.5 and we have another wave, then the government might be forced to reintroduce some minor public health measures.”
GPs also had a role to play, he told TMR.
“The government has removed the mandated face mask policy for health settings, but all GP practices should insist that patients wear face masks,” he said. “There are patients with underlying, major health issues which put them at risk. GPs would know who they are and they should be advising them when, how and what type of face masks to wear.”
