A health expert has called for free rapid antigen tests amid growing signs a fourth wave of COVID-19 infections is on the way ahead of the Christmas holidays.

Infectious disease expert Mary-Louise McLaws is concerned about an eightfold increase in case numbers on Thursday from the daily case average a month ago.

NSW registered a record 2213 cases and one death on Friday, its single biggest daily number of the entire pandemic, as the Omicron variant continued to cause concern.

"All of a sudden we have got the highest number we have had in NSW and I think this is sadly heralding a fourth wave," Professor McLaws told Nine on Friday.

"We really do have to be careful because what we have learnt from the England experience when Delta happened (was) all of a sudden children became the target for the virus and this is exactly what is happening again."

Children aged between five and 11 will be able to receive their first jab from January 10 next year.

"While adults may be vaccinated and feeling quite comfortable with living with (Omicron) children have not been vaccinated and they are at great risk of being the next big group (infected)," Professor McLaws said.

She called on the federal government to make rapid antigen tests available for free so people don't inadvertently spread the virus while travelling during the holidays.