The youngest Australians to be vaccinated against COVID-19 have received their first dose with the state's vaccination program opening for 5-11 year olds.

Laila Parker became one of the youngest Australians to be vaccinated against COVID-19, receiving her first dose as Sydney Local Health District began its vaccination program for children aged five to 11.

The five-year-old from Manly was one of more than 100 children receiving their first paediatric Pfizer dose at the NSW Health Vaccination Centre at Sydney Olympic Park on its opening day – and she didn't blink an eye.

For Laila's mum, Sarina Omal, the visit was a little more emotional.

"My mum is a nurse in a nursing home and my dad is a retired nurse, so we're a healthcare family. There was no question for us that Laila would be vaccinated. We know how important it is that we protect her and do our bit for the community."

Eight-year-old Mercer Wavde, from Randwick, came prepared with a home-made sign, holding it up for all to see as she proudly marched to the nurse's station.

"She's been looking forward to this so much," said Mercer's dad.

Vaccination Centre Medical Lead, Dr James Edwards, said it's great to see excited parents and children coming in.

"Vaccinating this group of children is a way to protect them, and protect the state," Dr Edwards said.

Vaccination Centre Operational Nurse Manager, Alison Wallbank said it was an important next step in our fight against COVID.

"I'm excited. This age group has really suffered through COVID, and I'm excited for my son to among those getting vaccinated today," Alison said.

"I think some parents will have reservations, but we have worked really hard to make the experience child friendly, with the family and child in mind, so I hope families will feel welcome.

With Sydney experiencing the ongoing threat of the spread of COVID, the District's Chief Executive Dr Teresa Anderson said the community response to the paediatric vaccine has been fantastic.

"As we continue to see a large number of COVID-19 cases in our community, it's great to see so many families coming in to be vaccinated. Appointments for both booster shots for adults and vaccinations for 5-11 year olds are filling fast at our vaccination centres," Dr Anderson said.

Vaccinations for children also opened today at the District's Koori Clinic at Redfern Town Hall and Canterbury Hospital with capacity to vaccinate about 1000 children a day across these sites.

In the coming weeks, additional sites will open to make more vaccination appointments available for five to 11 year olds. To make an appointment, go to vaccination.slhd.nsw.gov.au