Qantas has defended its decision not to allow cabin crew who developed COVID-19 after being stood down access to their accrued sick leave entitlements, arguing there is "no job for them to be sick from" and that many of them became infected while on holidays.

Key points: The ACTU says more than 50 direct Qantas employees have so far tested positive to coronavirus

The ACTU says more than 50 direct Qantas employees have so far tested positive to coronavirus The company is not offering sick leave entitlements to stood-down staff who later develop COVID-19

The company is not offering sick leave entitlements to stood-down staff who later develop COVID-19 Qantas's medical director said the majority of stood-down staff with the virus were infected while on holidays

The Australian Council of Trade Unions (ACTU) is calling for an immediate reversal of the decision, as a number of cases connected to the airline continues to grow.

More than 50 direct Qantas employees have now tested positive to coronavirus, the union said, with some passing it on to their loved ones.

One cabin crew employee has told the ABC they believe they contracted the virus while flying on an international route in March.

They said they started to feel sick within a week of returning home to Australia, and then tested positive to COVID-19.

"It was like a flu. I had a fever. Aches. Pains all over. And I lost my sense of smell," they said.

The cabin crew member said they were paid about four days of sick leave by Qantas before they were stood down, along with 20,000 other people employed by the airline.

After being stood down, they were not entitled to further accrued sick leave, and have been paid out of their accrued annual leave instead.

"It's all pretty ordinary," they said.

"I was there for work. Even if I got the virus while on the ground in the United States during my layover, I was still working for the company."

"I want to be paid for my time in isolation and compensation. They should give me my leave back."

Union accuses company of failing to uphold 'spirit of Australia'

The ACTU's president Michele O'Neil said that on Friday the 11-year-old daughter of a Qantas cabin crew worker had tested positive, after her mother tested positive too.

"This was something the cabin crew member was really fearful of," Ms O'Neil said.

"She was worried she wasn't given any paid accommodation to isolate away from her family and now her worst fears are realised with her asthmatic child having COVID-19.

"This is a very harsh, unacceptable way for Qantas to deal with workers who are trying to do their very best amongst this crisis.

"Qantas likes to talk about themselves as the 'Spirit of Australia'. This is not in the spirit of Australia."

Other cases include a group of baggage handlers at Adelaide airport who contracted the virus and then gave it to their families.

A spokesman for Qantas told the ABC that the Adelaide baggage handlers were paid out 14 days of sick leave after contracting the virus.

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They also confirmed that those who had been stood down were not able to access their accrued sick leave, because "there is no job for them to be sick from".

Instead, the stood-down workers should seek to access Job Seeker or Job Keeper payments while sick, the spokesman said.

Qantas has applied to the Federal Government for Job Keeper payments for its workforce, he added.

Company defends handling of self-isolation for staff

The airline is also claiming that few of its workers have actually contracted the virus while on the job, instead saying some contracted it while on layover in international countries between jobs on flights.

"There's been no confirmed cases of transmission of the Coronavirus to employees or customers on board our aircraft, or any aircraft globally for that matter," the airline's medical director Ian Hosegood said in a statement.

"In most of these cases, the employees have contracted the Coronavirus while overseas including staff who were on holidays.

"While the risk remains low, we have put in place increased measures to protect our people while they are at work and our customers including enhanced cleaning at airports and on aircraft and providing necessary safety equipment."

Qantas also defended its decision not to offer cabin crew free accommodation to self-isolate away from their families, because until two days ago Qantas staff were exempt from the mandatory 14-day quarantine laws.

"Qantas has fully complied with the requirements of Australia's Chief Medical Officer in relation to the quarantine exemptions for air crew," the spokesman said.

The airline now only has a skeleton crew still directly employed, who will staff humanitarian flights organized by the Federal Government out of international countries for Australians returning home.

Crew working on these flights will be required to self-isolate for 14 days on their return.

"They can elect to self-isolate at home or in a hotel. If a hotel, Qantas will pay and provide meals," the spokesman said.

Those that contract COVID-19 while on the job or come into contact with a confirmed case will also receive 14 days of self-isolation payments, they added.