Newly released mortality data shows one-third of Victorians who died with COVID-19 in the first half of this year were unvaccinated, despite the unvaccinated cohort making up just 4 per cent of the state's over-12 population.
Between January 1 and June 28 there were 2,171 deaths in the state related to COVID-19, just over half of the more than 4,200 such deaths recorded in Victoria since the pandemic began.
The data — provided to the ABC by Victoria's health department — showed that 799 people (37 per cent) who died during that period of time with COVID-19 had received no vaccine doses, while just 58 (3 per cent) of those who died had received four vaccine doses.
Those who had not received a third vaccine dose made up 72 per cent those who died with, or due to, COVID-19.
University of Melbourne epidemiologist Tony Blakely described the data as "interesting and unsurprising".
He said using a basic calculation, the data showed a person having one or more doses of a COVID-19 vaccine reduced their chance of dying by 93 per cent, compared with a person who had received no doses.
"There's more good news: If you've have three or four doses, your protection will be even higher than that," he added.
Vaccination status |
Deaths |
Percentage of overall deaths |
|---|---|---|
Unvaccinated/unknown |
799 |
37% |
One dose |
52 |
2% |
Two doses |
709 |
33% |
Three doses |
553 |
25% |
Four doses |
58 |
3% |
The department said that people whose vaccination status was categorised as "unknown" until it's established, usually make up about 3 per cent of deaths.
Of those who died, the median age was 85 years, while the median age of those admitted to hospital with COVID-19, as of June 28, was 76 years.
During the six-month period, 14,537 people were admitted to hospital with COVID-19 in Victoria, which represented less than 1 per cent of the 1.9 million cases diagnosed.
Monash University epidemiologist Associate Professor James Trauer said the data emphasised the need to focus on how to keep the most vulnerable people, such as the elderly, safe.
Vaccination rates among older Victorians remain among the highest, with 89.5 per cent of those aged 65 or over having had three doses, and 46.5 per cent having had a fourth dose.
Among all Victorians aged 16 years and older, 68.8 per cent have had three vaccine doses.
Vaccines still very effective against Omicron
Vaccines specifically targeting the Omicron variant are being developed, however, the existing vaccines are still highly effective.
The official advice from Victoria's health department remains that staying up to date with vaccines will "significantly reduce your chance of going to hospital, going to ICU or dying from COVID-19".
Professor Blakely said people should not wait and were better off getting a booster COVID-19 dose if they were eligible for one.
"They still work very well to stop you being hospitalised and to prevent death," he said.
"They're not as great at stopping any infection, but they do dampen transmission and, right at the moment, we're dealing with a surge of COVID."
Deakin University epidemiology chair Catherine Bennett said the data illustrated the power of vaccines.
"It really is a story of greatest risk of having serious illness and dying being inversely associated with the number of doses that you have had," Professor Bennett said.
She said there was no need to consider current boosters and the Omicron-specific vaccines being developed as exclusive choices.
"If people have a booster now it doesn't mean people can't have a booster later," she said.
"It's not to say you have one or the other, you can — potentially — have both."
Vaccination focus to shift over time
Dr Trauer said it was important not to lose sight of the importance of vaccine dose timing, not just the cumulative number.
"Over the coming years, as we see that this is increasingly becoming an endemic infection that people get exposed to every year, it's not going to be about have you had six doses or eight doses since the pandemic started," he said.
"It's going to be, going into a wave of transmission — if that's caused by a variant or a winter wave — 'Have you been vaccinated in the previous six or 12 months?'
"That's more going to be the question to determine risk of dying when you get re-exposed."
Many are unvaccinated by choice
Professor Bennett said understanding more about the remaining unvaccinated cohort could help curb the effects of the current wave.
She said many were unvaccinated by choice, but some in the group were unable to be vaccinated for medical reasons.
"There will be some people who were too frail or unwell to be vaccinated, who — unfortunately — were also at more risk of dying from COVID," she said.
Professor Bennett said the "really small" number of people who had experienced adverse reactions to COVID-19 vaccines were also represented in the data, but most in the group had just chosen not to get vaccinated.
"There are people who are unvaccinated by choice and they make up the majority of people in that unvaccinated group," she said.
"We want to make sure that everyone who, by choice, has not been fully vaccinated, understands that the story from this data is how protective vaccination can be."
Time to 'flatten the curve' once again
Professor Blakely said modelling predicted the surge of cases would not peak for another month, but people should remember that their actions were powerful.
"We control this. As a civic society, we can do things," he said.
"Getting a third dose if you haven't already had it, getting a fourth dose if you're eligible, wearing masks when you're in the supermarket.
"All those sorts of things will protect you and help flatten that curve."
He urged people eligible for anti-viral treatment to talk to their GP to plan what to do if they do contract the virus during this surge.
Professor Blakely said health services were going to be under pressure and the number of hospital admissions was likely to rise, given they lag about a fortnight after infection rates.
