REPEAT sewage samples taken at the Burwood Beach Wastewater Treatment Plant have not detected COVID-19, but health authorities say they "won't breathe easy" until further samples test negative for the virus.
Additional samples taken at the waste treatment works did not detect virus fragments, but the Hunter's public health physician, Dr David Durrheim said further samples would be collected for testing.
"It's still too early to celebrate," , said.
"We are hoping that the first detect was from a single individual, who came from overseas and completed their quarantine time, who may be shedding viral fragments.
"If it is only one person, the non-detect will probably be confirmed by the next two samples. But we will need a few negatives to be sure we are not missing any transmission in the community.
"We'd still encourage everybody with symptoms to be tested."
Dr Durrheim said they would do an extra test on Monday, followed by the regular weekly test on Wednesday.
NSW Health has thanked the Newcastle and Lake Macquarie communities for their "great response" to calls for COVID-19 testing after fragments of the virus that causes COVID-19 were recently detected in the Burwood Beach sewage catchment.
Hundreds of residents in Newcastle and Lake Macquarie fronted up for COVID swabs on Monday following the announcement of the sewage detection on Sunday.
In Newcastle, more than 740 Newcastle residents were tested for COVID-19 on Monday, while more than 370 people in the Lake Macquarie local government area were swabbed.
NSW Health said positive sewage results could indicate the presence of people - including returned travellers - who had recently recovered from COVID-19.
They could continue to shed fragments of the virus for up to four weeks.
Anyone with symptoms that could signal COVID-19, including a sore throat, runny nose, cough, fever, loss of taste or sense of smell, or a headache is urged to get tested and remain isolated until a negative result is received.
