Will the lockdowns and pandemic restrictions end for good once Australia reaches the 80 per cent vaccination goal?

That 80 per cent target has been touted as the 'magic number' to remove the need for harsh restrictions and border closures.

But, Professor Adrian Esterman, chairperson of biostatistics & epidemiology at the University of South Australia, told Australian Community Media (ACM) once Australia reaches that target, it's unlikely to eradicate the pandemic.

"The UK has over 90 per cent of their population with antibodies against the virus, so either they've been infected and recovered, or they've been vaccinated," Professor Esterman said.

"They still haven't achieved herd immunity. In Australia, it's simply not going to be possible."

The target is based on the Doherty Institute's model which hinges on the vaccination rate of people aged over 16.

But that accounts for just 63 per cent of the population when children under 16 are also counted.

"The previous modelling from the Grattan Institute has shown that we really need 80 per cent of the population, the whole population, to really do away with lockdowns," Professor Esterman said.

"It has to be much more like 100 per cent, or close to it before we can do away with lockdowns."

The number has been calculated by determining COVID-19's basic reproduction number, which is an estimation of how many people will be infected from a single source.

According to the calculation, if at the beginning of an outbreak there are, for example, 10 cases with a basic reproduction number of 1.1, then the outbreak will soon grow to just 11 cases.

But, if the cases rise to 400 as they did in NSW earlier this week, then the outbreak will soon multiply by 40.

So unless the infected parties maintain little contact with others, they have the potential to infect a lot of people.

The only way to bring the exponential growth number down is through rapid vaccination.

"But being vaccinated - fully vaccinated - does not give you that much protection, it might give you anything up to let's say 80 per cent protection," Professor Esterman said.

"That means you're going to need well over 90 per cent, probably near 100 per cent of people vaccinated and that simply won't be possible."

Currently, over 50 per cent of the nation has received a first dose vaccination, but that too may not be enough to protect against mutations in the virus, including the highly infectious Delta strain.

"What we've seen from Israel is that immunity wanes," Professor Esterman said.

"So at the start of the outbreak when people first got vaccinated in Israel, you were getting about 90 per cent protection against infection. It's now down to 44 per cent several months later."

To combat the changing virus booster shots are being developed, with many already en route to the USA and other nations that have already seen a high uptake in the original vaccine measures.

There is hope for the nation once that 80 per cent target has been reached, which Professor Esterman estimates will be reached roughly by the end of next year.

At this point, Professor Esterman said, it's likely the nation - and the world - will be able to live with COVID-19 transmission much more readily than is currently possible.

"Life will look [be] very much like with influenza, we will have the majority of people vaccinated and we know that a chunk of those people will still get it but it will be very mild, asymptomatic [or] with very mild symptoms and then even a few will get very sick and die," he said.

"Thousands of people die each year from influenza. So I think it will be a very similar situation, we will get annual booster shots, possibly jointly with influenza.

"By the end of this year, when we have the majority of Australians vaccinated, we'll need lockdowns less and less. Although we will not achieve herd immunity, we will achieve a dampening down of infections."