There have been active cases of COVID-19 in these areas, but the community is asked to act at the first sign of symptoms in case the samples are an indication of other, undiagnosed cases.

"High rates of testing are critical to ensuring that COVID-19 is not circulating undetected in the community,'' said Illawarra Shoalhaven Local Health District Director Public Health Curtis Gregory.

"Anyone feeling unwell - even with the mildest of symptoms - such as a runny nose or scratchy throat - must seek testing and self-isolate until they get their result.

"Stay at home, and do not go to work, the shops, or catch public transport until you receive a negative test result.''

Mr Gregory said that, while the detection of fragments could be explained by the known cases in Wollongong and Bomaderry, sewage testing was an important tool in providing early warning of any undetected infections.

The Wollongong sewage catchment serves 56,000 people in the suburbs of Lake Heights, Cringila, Warrawong, Brownsville, Dapto, Berkeley, Huntley, Horsley, Cleveland, Mangerton, Mount Saint Thomas, Unanderra, Spring Hill, Mount Keira, Figtree, Mount Kembla, West Wollongong, Kembla Heights, Cordeaux Heights, Farmborough Heights, Dombarton, Kembla Grange, Wongawilli, Coniston, Wollongong and Port Kembla.

The Bomaderry sewage catchment serves 18,000 people in the suburbs of Bomaderry, Cambewarra, Cambewarra Village, Meroo Meadow and some parts of North Nowra.

Anyone who lives or works in any of these areas should be particularly vigilant for the onset of symptoms that could signal COVID-19. If even if the mildest of symptoms appeared, it was important get tested immediately and isolate until a negative result is received.

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