Based on a population of 140,000, the current double-dose vaccination rate would be 81 per cent.
Furthermore, if the 2019 population estimate of 168,000 continues to be used, the highest possible double-dose coverage will be about 83 per cent even if every one of those 140,000 current residents gets vaccinated.
The data lag will have practical implications for City of Melbourne residents within weeks: once South Australia reopens its border on November 23, visitors coming from a local government area where less than 80 per cent of the population is fully vaccinated will be required to quarantine for seven days.
Ms Sandell said inner-city Melburnians had been increasingly contacting her worried they would not be able to do things like going interstate because the vaccination rates were inaccurate.
“It’s important the government gives us more accurate vaccination data, so that residents can have confidence and do things like travel interstate, but also so the government can better target any extra vaccination efforts,” she said.
Cr Capp said her council had raised the inaccuracy of the vaccination data with the Commonwealth on multiple occasions since August.
“No other municipality has done more than City of Melbourne to help its community get vaccinated including multiple incentive campaigns,” she said.
In a statement, the Victorian Health Department confirmed vaccination rates for people aged 18 to 25 in the City of Melbourne appeared to be significantly below the state average, suggesting a drop in the number of students.
Before the pandemic, international students made up about one-third of the council’s residents.
In Carlton, home to multiple student accommodation buildings near RMIT and the University of Melbourne, state data from last week suggest the single-dose coverage is just 55 to 60 per cent and 45 to 50 per cent for both doses.
In the CBD, that rises slightly to 70 to 75 per cent single-dose coverage and 55 to 60 per cent for both.
Monash University demographer Rebecca Kippen said while it was difficult to put a figure on how much the City of Melbourne’s population had dropped, it was clearly being overestimated following 18 months of “huge demographic upheaval”.
According to the Australian Bureau of Statistics’ latest state-by-state update from March, Victoria’s population dropped 43,000 year-on-year. Dr Kippen said it was probable a reasonable proportion were city residents.
In another example of outdated data skewing vaccination rates, Dr Kippen said Canberra was on track to exceed 100 per cent vaccination because the capital’s population had grown since 2019.
She said the clearest solution would be to use data collected in August’s census, which is not due for public release until June next year.
“It would be an enormous amount of work to process some of that census data ahead of time. However, now we are in a situation where states are basing policy on these estimates, I think that would be worthwhile,” she said.
She also questioned why population figures from June 2019 were being used rather than June 2020. Data for June 2021 will not be released until the second half of next year.
A spokesman for the federal Health Department confirmed the use of 2019 data but did not respond to questions on when or how it would be updated.
Ms Sandell added that she had written to the Victorian health department asking them to set up more mini pop-up clinics in places city residents will increasingly visit as the state reopens.
A state health department spokesman said mobile vaccination vans and a clinic at Melbourne Town Hall for international students and people facing disadvantage were improving the city’s vaccine uptake.
“Melbourne is home to many young and diverse communities – including some of our most vulnerable,” he said.
“We’re doing everything we can to boost vaccination rates, get doses to where they’re needed and give people the support they need.“
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