NSW Health Minister Brad Hazzard has taken aim at those yet to receive all of their available Covid-19 vaccine doses as daily cases once again top 10,000.
More than 30 per cent of eligible residents in the state have not yet received a third jab, with Mr Hazzard calling them "crazy" on Tuesday.
He said 1,232 people who had not received a booster have died from Covid-19 in 2022, calling such a fatality rate "a critical issue", especially as cases are starting to rise once again.
Mr Hazzard said evidence suggests vaccines are not preventing the "pesky" BA4 and BA5 variants from spreading in the state, however he said being fully vaccinated reduced the chances of illness and death.
"If you haven't your full three, to put it bluntly, you're crazy," he told reporters.
"You should go and get them. That's what is going to make a difference to stopping or at least reducing the chances of you ending up in hospital or ending up possibly dying.
"I can't stress this enough."
Covid-19 cases in NSW continue to climb
On Tuesday, NSW reported 10,504 daily infections, the fifth time in the last week cases surpassed 10,000.
Prior to the last seven days, daily cases had not surpassed that marker since May.
Mr Hazzard warned the state could be seeing similar activity to January where cases rapidly spiralled to more than 30,000 cases a day.
And Queensland recorded its biggest daily spike in Covid cases on Tuesday for over six weeks with 5,698 new cases recorded.
The BA4 and B5 variants are responsible for a 30 per cent spike in cases in the UK, health authorities say.
In the UK, positive cases no longer have to isolate from the community.
The World Health Organisation said this week that Covid-19 is increasing in more than 100 countries worldwide.
The UN health agency warned that relaxed testing and surveillance measures mean it may be more difficult to catch emerging variants before they spread more widely.
Do you have a story tip? Email: firstname.lastname@example.org.