"We are monitoring very closely the situation in Sydney and the potential bearing it could have on our region," Mid North Coast LHD Chief Executive Stewart Dowrick said.

"The re-emergence of COVID-19 cases in Sydney has led to a significant increase in testing here on the Mid North Coast over the past fortnight.

"To give you an indication of how dramatic this daily rise has been, on Wednesday 16 December there were 51 COVID-19 tests conducted at our MNCLHD clinics across the district, just five days later on 21 December there were 719.

In addition to increased oral swab testing, Macleay sewage is now also being tested for fragments of the virus.

The first tests were conducted the week before Christmas.

"Sewage testing is being undertaken on the Mid North Coast and has been in our major centres of Coffs Harbour and Port Macquarie for some time," Mr Dowrick said.

"Additional testing sites have come on board in recent weeks (Nambucca, Bellingen, South West Rocks, Crescent Head, Bonny Hills and Dunbogan) but there have been no detections."

Testing sewage is a handy way to track infections in the community and alert authorities to an increase in infections.

"An infected person can shed virus in their faeces even if they do not have symptoms, and shedding can continue for several weeks after they are no longer infectious," NSW Health's weekly epidemiological report said.

But the sewage surveillance is currently acting only as support for the ongoing testing work each LHD is conducting.

"For example, it is not currently known the minimum number of cases that can be detected in a catchment. A small number of cases in a large sewage catchment may not be detected by sewage surveillance due to factors such as dilution, inhibition, reduction in shedding over the infection period or movement of cases," the report said.

Mr Dowrick said our healthcare workers had been rallying to the call for more help since the Sydney outbreak.

"Over the Christmas break I have been visiting our COVID-19 clinics to personally thank the healthcare workers who have answered the call for extra assistance during this busy time," he said.

"These clinics have continued to serve their local communities with testing and the latest public health advice, always delivered in a friendly and professional manner.

"Our frontline staff have been working hard over the past 11 months to keep our community safe and we are mindful of ensuring their health and wellbeing at all times."

He also had praise for the Macleay Valley community.

"Thanks to the community for working with us to ensure we remain COVID-free. By keeping your distance, washing your hands and getting tested (even if you have only one mild symptom) you're making a difference," he said.

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