Central Coast Local Health District (CCLHD) knew about a cluster of COVID-19 cases linked to a Peats Ridge hydroponics farm for almost a week in early August, but did not release the information publicly.

Seven people from south-west Sydney who worked on the farm tested positive to coronavirus after sharing private transport to the Central Coast.

Health authorities only confirmed the cases after repeated requests from the ABC on Friday, August 7, five days after contact tracing had begun and seven days after the farm had closed due to coronavirus concerns.

Central Coast Health says it informs the community when COVID-19 is confirmed in local residents.

Professor of Epidemiology at UNSW Mary-Louise McLaws said nothing justified non-disclosure.

“It helps us to cooperate with the authorities, to understand how individual responses can cause a cluster.”

Reports of the cluster linked to the hydroponic farm, which the ABC has decided not to name, first came to light in a leaked internal email.

The ABC has since learnt that the farm closed on July 30 after a farm employee was found to have been in close contact with a confirmed case.

Two days later on Sunday, August 2, several farm employees had tested positive to COVID-19.

The business then began liaising with NSW Health and Central Coast Health on contact tracing.

Two managers that reside on the farm tested negative and self-isolated for fourteen days as a precaution.

Public confidence undermined

Professor McLaws, who advises the World Health Organisation on COVID-19 policy, said the non-disclosure undermined public confidence in authorities.

“If we find out we have not been told about a cluster or numbers then we cannot have full confidence in the numbers that we’re being told, or the level of risk for the public, and therefore the importance of cooperation,” she said.

Professor McLaws said she hoped important public health lessons were taken from the outbreak.

“If you’re going to share a ride you have to wear a mask and you have to be able to sit in a vehicle where you have enough space. That doesn’t mean four or five people in a car,” she said.

Local member didn’t know of cluster

The hydroponic farm is in the Gosford electorate and local member Liesl Tesch knew nothing about the COVID-19 link to the Central Coast.

“When the government’s withholding information it just feels like we’re not all in this together,” she said.

Parliamentary Secretary for the Central Coast Adam Crouch has defended the approach of health authorities.

“I have complete faith in the [CC]LHD staff to communicate the necessary health advice and precautions to our community when required,” he said.

Neither Central Coast Health, nor the law firm representing the farm, responded to questions from the ABC concerning whether masks were being worn during transportation, or if any new procedures have been implemented since the outbreak.