An aged care nurse has been fined $25,000 after working casual shifts at a facility in Highett while positive for COVID-19.

The nurse was sentenced in the Moorabbin Magistrates' Court after pleading guilty to a single charge of failing, as an employee, to take reasonable care for the health and safety of persons at the workplace.

The court heard that on 26 and 27 July 2020, the nurse reported for casual work shifts at an aged care facility in Highett after a doctor had advised her not to go to work and referred her for a COVID-19 test.

On both occasions, she completed the mandatory staff temperature and declaration log stating that she did not have any of the listed COVID-19 symptoms.

The nurse subsequently undertook a PCR swab test for COVID-19 on 28 July 2020.

Two days later, she was informed that she was positive for COVID-19 and was again directed by her doctor to isolate and not go to work.

On 1 August 2020, management at the Highett aged care facility was informed that a resident had tested positive for COVID-19.

The resident was immediately sent to hospital, other residents were isolated to their rooms, and all staff were directed to wear full PPE with the immediate establishment of PPE stations throughout the workplace.

The following day, the nurse again attended the workplace for an evening shift.

WorkSafe Executive Director Health and Safety Narelle Beer said the nurse had clearly failed to take reasonable care for her colleagues and residents at the facility.

"Every worker in Victoria has a duty to ensure their actions do not put the health and safety of others in their workplace at risk," Dr Beer said.

"This includes cooperating with their employer's efforts to control health and safety risks by following any instructions, policies and procedures and using supplied protective equipment."