An infectious diseases expert is warning NSW could be headed for a lockdown if the COVID-19 outbreak worsens.

Greater Sydney is under restrictions for the next week after four mystery cases were part of the 16 recorded yesterday.

Infectious diseases expert at Griffith University Professor Nigel McMillan told Ben Fordham the measures are “fairly sensible” but if the numbers keep rising a lockdown should be considered.

“If these numbers keep doubling up it really can get out of hand quite quickly.”

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