Mask-wearing must be mandated in NSW high schools, an education union says, as the number of cases linked to the state's students continues to grow.
NSW health authorities are still working to trace the source of a 17-strong coronavirus cluster developing at an independent Catholic school in northwest Sydney.
At least six of the state's 22 new COVID-19 cases on Tuesday were linked on to Tangara School for Girls in Cherrybrook.
It's the highest daily increase of COVID-19 cases in NSW for almost four months, with 17 locally acquired cases being the highest number in that category since late July.
The Independent Education Union says a move to mandate mask use for students and staff at senior schools is needed to prevent further outbreaks in schools.
"The IEU is concerned that our members and the young people in their charge are being told there is something exceptional about passing through the school gates that means the COVID-safe precautions we are all undertaking out in the wider community need no longer apply," IEUA NSW secretary Mark Northam said in a statement on Tuesday.
The Opus Dei-associated Tangara has closed its secondary campus until August 24 and its junior campus until at least Wednesday after its first COVID-19 case last week.
Another primary school, Parramatta Public School, will close on Wednesday for deep cleaning after a student tested positive to COVID-19.
Tangara School for Girls in Cherrybrook, northwest of Sydney, Tuesday, 11 August, 2020. Source: AAP
In western Sydney, Bonnyrigg Heights Public School reopened on Tuesday after being closed for cleaning on Monday, but Kids' Early Learning Quakers Hill remains closed after children were exposed to the virus.
A second student at Our Lady of Mercy College in Parramatta has also caught COVID-19.
After three weeks with no new COVID-19 cases linked to the Batemans Bay Soldiers Club cluster in NSW's south, the local high school and public school were also both closed on Tuesday after one student at each tested positive for the virus.
Premier Gladys Berejiklian said the state remained on high alert after its biggest daily growth of cases since April 16.
"We are in a pandemic - every organisation, every entity needs to abide by the COVID-safe plans," Ms Berejiklian told reporters on Tuesday.
"My anxiety has not subsided in relation to what a knife edge NSW is on, but we need to keep pulling together and keep doing the right thing.
People in Australia must stay at least 1.5 metres away from others. Check your state’s restrictions on gathering limits.
If you are experiencing cold or flu symptoms, stay home and arrange a test by calling your doctor or contact the Coronavirus Health Information Hotline on 1800 020 080.
