How an airport limousine driver caught coronavirus before sparking a outbreak that sent Sydney into lockdown may never be known, health chiefs warn.
NSW Chief Health Officer Kerry Chant said the limousine driver could have picked up the virus while transporting international flight crew from Sydney Airport.
'We have reached out to the flight crew organisations, places like FedEx and others and asked them whether any of their flight crew had tested positive,' she said.
The New South Wales chief health officer has warned authorities may never know how an airport limousine driver acquired Covid-19 before sparking the latest outbreak in Sydney