Sydneysiders in 14 suburbs are put on coronavirus alert after the killer disease was discovered in sewage

Sydneysiders in 14 suburbs have been urged to monitor for symptoms of Covid-19 and get tested if they appear after the virus was detected in sewerage.

NSW Health issued the warning on Wednesday after their sewerage surveillance program detected fragments of the virus at the West Hornsby Wastewater Treatment Plant in Sydney's northwest.   

This catchment takes in the suburbs of Glenorie, Wahroonga, Thornleigh, Pennant Hills, Cherrybrook, Castle Hill, Galston, Dural, Westleigh, Glenhaven, Waitara, Hornsby, Normanhurst and West Pennant Hills. 

Socially-distanced office workers in Sydney on Wednesday. NSW Health issued the warning on Wednesday after their sewerage surveillance program detected fragments of the virus at the West Hornsby Wastewater Treatment Plant in Sydney's northwest

'Everyone in these areas is asked to be alert for symptoms, to get tested immediately if they appear and then isolate until they receive a negative result,' NSW Health said. 

'The presence of SARS-CoV-2 in sewage may reflect the presence of known cases of Covid-19 diagnosed in recent weeks in the areas served by this sewage treatment plant. 

'However, NSW Health is concerned there could be other active cases in the local community in people who have not been tested and who might incorrectly assume their symptoms are just a cold.' 

New South Wales recorded only one new local case of coronavirus on Wednesday.  

The case is linked to the Berala cluster in western Sydney and is a close contact of previously reported cases.  

Premier Gladys Berejiklian was confident the cluster had been contained, saying: 'We are definitely in the mop-up stage.' 

A health care worker is seen at a COVID-19 pop up testing clinic at Castle Hill Showground There were 20,664 tests reported to 8pm on Tuesday night, compared with the previous day's total of 14,738

There were 20,664 tests reported to 8pm on Tuesday night, compared with the previous day's total of 14,738. 

Six cases were recorded in hotel quarantine. 

Ms Berejiklian said restrictions will not be eased just yet. 'If the advice to me and the government is we can ease restrictions we've put in place, we will do that,' she said.

'But until such time as we've mopped up the current outbreaks, I think everybody appreciates what we're doing and I want to thank everybody for their support and cooperation on this journey.' 

New South Wales recorded one new case linked to the Berala cluster on Wednesday. Premier Gladys Berejiklian was confident the cluster had been contained, saying: 'We are definitely in the mop-up stage.'

Masks were made mandatory and home gatherings were limited to five visitors after an outbreak on the Northern Beaches of Sydney was identified on December 16 and another cluster emerged in western Sydney on December 29. 

Asked if any rules would be relaxed this week, the premier said on Tuesday: 'Unlikely given where we're at, because we're still mopping up.

'We're still seeing community transmission. Even though in most instances, the household contacts or people are already in isolation, but we have had a couple of examples where they're still unlinked, and that's always a concern.'

She added: 'I doubt there will be an easing of restrictions. But if the health advice changes on that, we will, of course, do that.' 

What are the coronavirus rules in Greater Sydney? 

Visitors: Up to 5 visitors from any number of households may visit another on any day.

Gatherings: No more than 30 people can gather outside in a public place which includes public parks, reserves, beaches, public gardens and spaces. 

Masks: Compulsory in public indoors 

Venues: A maximum of 300 people, subject to the 1 person per 4 square metres rule applies for each separate area of a hospitality venue.

Nightclubs: Closed

Singing: No more than five performers should sing indoors, with 1.5m between performers and 5m between performers and the audience.

Gyms: Indoor gyms are subject to the one person per 4 square metres rule. A maximum of 30 people per class applies to gym and recreation classes such as yoga, tai chi and pilates.

Sport: For community sporting activities that involve more than 100 participants, the organiser must have a COVID-19 Safety Plan. The maximum number of participants at a community sporting activity must not exceed 3000 participants, or one person per 2 square metres (whichever is less). 

Source: NSW government