Australians are being urged to get COVID-19 booster shots as early as possible amid concern many double-vaccinated people may have almost no protection against the omicron variant.

With Queensland opening its borders on Monday – prompting a retaliatory crackdown by Western Australia’s government on visitors from the sunshine state – Health Minister Greg Hunt on Sunday said there would be a Commonwealth campaign to raise awareness of the need for boosters in the lead-up to Christmas.