Health officials in New South Wales are among the first in Australia to join their New Zealand counterparts in declaring a new wave of COVID-19 cases that is expected to be just as pervasive, if not worse, than when the Omicron variant first arrived on Australian shores earlier this year.
On Tuesday, NSW chief health officer, Dr Kerry Chant, joined the state’s health minister, Brad Hazzard, to call on residents around the state to go “back to basics”, mask up, and get vaccinated, in the face of a wave of new cases linked to the arrival of the Omicron BA.4/BA.5 variants. The new surge in cases is expected to peak in late-July or early-August.
“It is essential that you stay up to date with vaccinations,” Dr Chant told reporters. “Disregard everything we’ve said about two doses—it’s three doses or more.”
During the 24 hours to 4p.m. on Monday, there were 1,782 COVID-19 hospitalisations across the state, of whom 58 were in ICU with the virus, as a result of 10,504 tests. Fourteen people died, according to NSW Health.
The press conference comes more than six months after some residents with early vaccine eligibility received their third jab, and as experts from across the medical community ramp up pressure on the Australian Technical Advisory Group on Immunisation (ATAGI) to open up eligibility for a fourth dose.
Even still, the state’s third-dose vaccine uptake has been relatively low. According to the state’s health department, 95.1 percent of people over the age of 16 have had two doses of the vaccine, while just 68.1 percent of those who are eligible had their third.
“If you haven’t had your full three, put it bluntly, you’re crazy,” Hazzard said.
“That’s what is going to make a difference to stopping or at least reducing the chances of you ending up in hospital or ending up, possibly, dying. I can’t stress this enough. I think there are some in the community who are just very busy, there’s others in the community who think the pandemic is over,” he said.
“On both of those counts, they’re wrong.”
Even though third-dose uptake has been slow in NSW, both Hazzard and Dr Chant called on ATAGI to open up eligibility for fourth doses, if there aren’t any supply restraints, in the face of the arrival of Omicron’s new sub-variants.
They also called for looser restrictions on antiviral medication, which is currently subject to prescription access restrictions.
As it stands, the Therapeutic Goods Administration (TGA) has only approved two oral antiviral treatments for COVID-19 in Australia, Lagevrio and Paxlovid, which are both available in NSW.
Health officials in NSW aren’t alone in issuing foreboding warnings on the re-emergence of staggering case numbers through the height of winter.
Just across the Tasman, health officials and medical experts in New Zealand have been issuing warnings of their own. On Monday, health experts also pointed to signs of a new wave of Omicron cases, after the new BA.4/BA.5 Omicron subvariant grew to prominence across the country over the last week.
Like their New Zealand counterparts, NSW health officials have been quick to quash questions over the reintroduction of mask mandates in public, for fears of prolonged mental health impacts, and any number of other factors, Hazzard said, like “children’s cognitive development”.
Mask mandates are currently in place on public transport across the state, and residents are encouraged to wear them in “indoor spaces, at the shops, and in pharmacies”, Dr Chant said, even though they aren’t compelled to.
Health officials around the country have issued renewed warnings state-to-state, but those in NSW have been most definitive in forecasting a malicious caseload. Late last month, Queensland’s chief health officer, Dr John Gerrard, said he expected Omicron’s BA.4/BA.5 strain to be the dominant sub-variant seen across the state in the coming weeks.
Only days later, Victoria’s chief health officer, Brett Sutton, said the state’s health department had discovered that traces of the BA.4/BA.5 strain in Victoria’s metro and regional wastewater “have risen significantly in recent weeks, indicating increasing transmission of this sub-lineage in the community”.
“The Department of Health anticipates the prevalence of BA.4/BA.5 in Victoria is likely to result in an increase in cases, including reinfections, and hospital admissions,” Sutton said in a statement.
“This is because the strain has a greater ability than BA.2 to evade immunity provided by vaccination and earlier COVID-19 infection.”
According to the evidence available so far, the BA.4/5 strain could be the most transmissible COVID-19 subvariant seen yet. The reproduction number, or “R0”, for the new subvariant is incredibly high, according to a pre-print publication from South Africa, which puts it at about 18.6.
That’s a rate similar to measles which, up until now, was the most infectious viral disease known to man.
By comparison, the original Wuhan strain has a reproduction number of just 3.3, while Delta’s was 5.1, and the original Omicron variant, now known as BA.1—which caused havoc on arrival in Australia—had a reproductive number of only half that of this new subvariant, at 9.5.
The severity of the disease still remains a relative unknown. Another South African pre-print publication from a Japanese research group found that BA.4/5 was able to replicate more efficiently in the lungs than the earlier BA.2 sub-variant. When tested on hamsters, it developed into more serious illness.
Early data from South Africa and the United Kingdom, though, found that the BA.4/5 wave didn’t lead to a marked increase in severe disease and death.
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