The Melbourne Institute's fortnightly report card into vaccine hesitancy shows it has fallen, from 33 per cent at the end of May to 21.5 per cent last Friday.

The sharp drop in hesitancy over the past eight weeks is across all states and age groups.

With Greater Sydney and its surroundings enduring a fourth week in lockdown, vaccine hesitancy rates in NSW are at 14.6 per cent.

That has more than halved since late May and the authors of the report cite a sole reason.

"The outbreaks are clearly changing some people's minds about getting vaccinated, especially in NSW," said the report, published on Wednesday by the leading economic and social policy research institution.

Some 11.8 per cent of the 1200 Australian adults surveyed are still refusing to get a coronavirus jab, while 9.7 per cent remain unsure - down from 15 per cent at the end of May.

The report said the latter group is most likely to be affected by policy, with the nation's expert panel on immunisation last week revising its advice to recommend Sydneysiders "strongly consider" receiving the AstraZeneca shot in response to the worsening outbreak.

Despite the latest outbreaks reinforcing the benefits of getting the jab, high rates of vaccine hesitancy persist among those aged 18 to 44 (28.8 per cent) and Queenslanders (30.9 per cent).

"Policies to reduce vaccine hesitancy need to be carefully targeted at populations most vulnerable and most likely to transmit the virus, as well as geographic areas with the lowest vaccination rates," the University of Melbourne-based institute said.

VACCINE HESITANCY BY STATE

* NSW - 14.6 per cent, down from 32.9 at the end of May

* Victoria - 23.88 per cent, down from 32.12

* Queensland - 30.83 per cent, down from 38.69

* South Australia - 23.91 per cent, down from 30.85

* Western Australia - 21.38 per cent, down from 29.01

* Other - 11.04 per cent, down from 22.86

Australian Associated Press