The latest geographic vaccine data released on Monday shows some of South Australia’s most populous local government areas have vaccination rates 15 to 30 points lower than Adelaide’s inner eastern and southern suburbs.

Playford, which has an over-15s population of more than 72,000 people, had just 33.7 per cent of over-16s fully vaccinated as of Sunday.

Similarly, only 39.4 per cent of over-16s in Salisbury are fully vaccinated. The northern suburbs LGA has an over-15s population of more than 114,000.

By contrast, Burnside reached a double dose rate of 63.9 per cent on Sunday – the state’s highest rate ahead of Victor Harbor (60.6 per cent) Mitcham (60.3 per cent), Holdfast Bay (60 per cent) and the Adelaide Hills (59.5 per cent).

The wide disparity between regions comes as Premier Steven Marshall reiterated this week that South Australia needs an “equitable” distribution of vaccination rates once the state reaches the national 80 per cent double dose target.

University of South Australia epidemiologist Professor Adrian Esterman said uneven vaccine take up is posing a problem to all jurisdictions.

“The issue here is that you don’t really want to reopen until everybody’s had a chance to be fully vaccinated,” he said.

“The way to go about that is to now start prioritising those areas with low vaccination coverage, providing more places people can get vaccinated [and] better messaging.

“Because if you don’t do that, what you’re going to end up with is you start getting huge pockets of infections in those areas which have got poor coverage.”

Esterman said messaging on vaccines, particularly within migrant communities, would be crucial to levelling the vaccination rates.

“If the government really does want to get an even balance of vaccination rates across South Australia, they’ve got to pull out all stops to get the messaging right and to persuade the people in those areas like Playford that it’s incredibly important that they do get vaccinated,” he said.

“It is doable, it’s just a matter of is the government willing to put the effort into doing that.”

Deakin University Chair of Epidemiology Professor Catherine Bennett said outbreaks in unvaccinated communities could move rapidly once South Australia reopens.

“If you do have a concentrated area – either geographically or networked through workplaces or social or religious connections where you have a particularly low vaccination rates – then you’ve still got the vulnerability in that community,” Bennett said.

“The chances are, if not immediately, but eventually the virus will find its way there.

“The big problem then is that an outbreak will take off quickly because we know how quickly Delta works, and you have, say, half the population – potentially adult population – who are still at risk of serious illness.

“That’s what we want to protect all communities from.”

South Australia today passed 50 per cent double-dose vaccination for over-16 and is soon set to hit the 70 per cent first dose milestone.

On current pace, the state is forecast to reach 80 per cent double dose vaccination by early December, according to an analysis by ABC News.

Bennett said the question of whether lower vaccination rates in the northern suburbs would impact South Australia’s reopening timetable depends on demographic factors.

“You can’t really look at this without looking at it in an age specific way,” Bennett said.

“If you had slightly lower [vaccination] rates being young adults, you might be less worried than if you had only 50 per cent of people over-70 vaccinated.

“So all of that makes it quite a complex calculation, but that’s what health departments will look at, not just the overall averages or LGA averages.

“There’s no magic formula that we can all watch and make sure we’ve got there.”

Chief public health officer Nicola Spurrier told ABC Radio this morning that SA Health is conducting state-specific modelling looking at “a whole variety of scenarios”.

She said SA Health’s current models, based on the outbreaks in NSW and Victoria, forecast South Australia will be dealing with 4000 active cases after the borders reopen.

“One of the other major policy questions in my mind is how do we open the border in a safe way,” she said.

“If you look at the Doherty modelling, the way to be able to reopen at the 80 per cent [is] you have to have that contact tracing, quarantining and isolation.

“So we’re doing a lot of work at the moment making sure we’ve got enough staff and our IT systems are up to scratch.

“We will need to have some public health and social measures in place … because without that, some of the other parts of this won’t work despite vaccination.

“Vaccination changes the game for us but the other thing that’s changed the game is the Delta variant, because it’s so much more infectious and more transmissible, we will need to have all of those parts together for us to manage this going forward.”

While lower vaccination rates in Adelaide’s northern suburbs could delay South Australia’s reopening timetable, local mayors are confident uptake in their LGAs will eventually catch up with the rest of the state.

Playford Mayor Glenn Docherty said some of the slower uptake was due to the northern suburbs having a younger population profile.

“Playford and Salisbury generally have a younger demographic than the state average, so of course when vaccination first started those age groups weren’t eligible,” he said.

“Those cohorts are now eligible, and obviously there is a bit of lag in catching up and making bookings.”

The area’s main clinic, the Playford Civic Centre mass vaccination hub in Elizabeth, is open seven days a week from 9am to 4pm.

Docherty said extended opening hours at the clinic would benefit the area’s shift workers.

“I think there does need to be some extended opening hours of the Playford vaccination hub,” he said.

“While they do a fantastic amount of work, they’re doing great work, it would be great to see those opening hours extended earlier in the morning and also later in the evening to allow those on shift work and others to book appointments.

“I think hubs or dedicated strike teams in suburbs or in areas that have lower vaccination rates for a variety of reasons could be considered by the government.

“But I am suspecting when those new statistics come out [on Monday], you will see a bump in the vaccination rate.”

The Playford Mayor also pointed to improved communication with the area’s migrant communities as a reason for optimism.

“With our new and emerging migrant communities … getting the relevant message out through their community leaders has been something that the government’s worked on earlier,” he said.

“And now we’re seeing increased community action in relation to getting vaccination.”

At the other end of the spectrum, City of Salisbury Mayor Gillian Aldridge attributed the slower pace of the rollout in her council area to older people waiting for the Pfizer vaccine.

“A lot of the people in this area of a generation over 60 or 70 wanted to have a choice and now they’ve got that choice – and they’re literally streaming in,” she said.

People over the age of 60 became eligible for the Pfizer vaccine in South Australia on Monday, September 13.

On that day, 35,000 appointments were made at state-run clinics across the state, according to SA Health.

About 11,000 of those bookings were made for children aged 12 to 16 who also became eligible on September 13.

Aldridge said the acceptance of walk-in appointments at state-run clinics has also improved the rollout.

“I think Salisbury is reasonably good compared to perhaps out further north,” she said.

“We all work so incredibly hard and often you don’t have an hour to go to some clinic and wait, now you can walk in.

“I’m very confident the numbers are really going to be streaming in by the end of this week.”

An SA Health spokesperson said the agency was “constantly” looking to increase the state’s vaccination capacity and highlighted the State Government’s decision last month to open a new vaccine clinic in Pooraka.

The clinic, located at the SA Produce Market, is offering 1500 Pfizer vaccines a week.

“It is pleasing to see 50 per cent of South Australians aged 16 or over already fully vaccinated and we are on track to reach the 80 per cent mark before the end of the year,” the spokesperson said. 

“We are monitoring vaccination rates closely and constantly looking to increase the capacity to vaccinate South Australians against COVID-19 with new vaccination clinic locations being explored and launched, most recently at Pooraka.”

Health Minister Stephen Wade said the State Government was continuing to “scale up clinics, open new clinics and deliver outreach vaccination programs to reach pockets of the community with lower vaccination rates”.

“It is not only critical that we drive up statewide vaccination rates, but that we ensure strong vaccination rates across geographical and cultural cohorts across the state,” Wade said.

“SA Health is also working with industry to support workplaces to vaccinate their staff, particularly in low vaccination areas or businesses with a high CALD workforce, as well as a school vaccination program to support 12-15 year olds and families to get vaccinated.”