NSW authorities have issued a warning for a gym in Sydney’s south-west where a positive coronavirus case visited more than a dozen times in the past fortnight.

NSW Health said the person visited the F45 gym at Leppington 13 times between October 15 and October 28.

The warning comes as NSW recorded its first mystery coronavirus infection in more than a fortnight, while the Hoxton Park campus of the Malek Fahd Islamic School – in Sydney’s south-west – was closed after two students tested positive.

Health authorities in NSW on Thursday confirmed four new locally acquired coronavirus infections.

The confirmed case linked to the F45 gym is among the new cases reported in Thursday’s numbers.

NSW Health considers anyone who attended the gym at the following times to be a close contact. They must get tested for the virus immediately and isolate for 14 days from exposure, regardless of the result:

• Thursday, October 16, from 5.15-6pm
• Saturday, October 17, from 8.10-9.10am
• Sunday, October 18, from 8.55-9.40am
• Monday, October 19, from 5.50-6.35am
• Tuesday, October 20, from 5.50-6.35am
• Wednesday, October 21, from 5.15-6pm
• Thursday, October 22, from 6.45-7.30am
• Friday, October 23, from 9.35-10.20am
• Saturday, October 24, from 7.10-8.10am
• Sunday, October 25, from 8.55-9.40am
• Monday, October 26, from 5.50-6.35am
• Tuesday, October 27, from 6.45-7.30am
• Wednesday, October 28, from 5.50-6.35am

Elsewhere, Queensland Premier Annastascia Pałaszczuk is to announce a decision on reopening her state’s borders on Friday.

The closure to NSW residents has come in for particular criticism from NSW Premier Gladys Berejiklian. Ms Pałaszczuk’s decision comes a day before Queenslanders vote in their state election.

-with agencies