About 50 Qantas and Jetstar staff, including pilots and cabin crew, have tested positive for coronavirus, the airline group confirmed.
The company's medical officer Russell Brown yesterday told staff that, in addition to previously announced cases of baggage handlers, the airlines' numbers included eight pilots and 19 cabin crew.
"Most of those were from overseas, but they were taking the precautions," Dr Brown said via a webinar.
"They are wearing masks when flying and being careful, and we're still seeing these cases.
"When you're dealing with a community that has more spread, the risk goes up, and we have to start thinking about what's going on here."
It is understood the cases have been distributed throughout the entire Qantas Group - which also includes Jetstar.
In a statement, Qantas medical director Ian Hosegood said there was no evidence passengers had caught the virus from infected staff - but could not rule that out.
"In most of these cases, the employees have contracted the coronavirus while overseas including staff who were on holidays," Dr Hosegood said.
"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."
All of the infected staff members are undertaking 14 days' quarantine.
Security worker now among Adelaide Airport cluster
It comes as the cluster of coronavirus cases at Adelaide Airport continues to grow, with management confirming a security worker who carries out public duties has COVID-19.
Adelaide Airport management said it was now working with SNP Security and SA Health.
The latest positive case comes after 12 Qantas baggage handlers also tested positive, while seven family members have been infected through close contact.
SA Health has advised anyone with COVID-19 symptoms who has been to the airport including the car park in the past fortnight to self-isolate and get tested.
On Tuesday, Qantas cancelled seven Adelaide flights, including one that was turned back to Sydney mid-air.
South Australia's chief public health officer Nicola Spurrier said SA Health had also made recommendations about the baggage handling area.
"Our department's worked with Qantas overnight to give advice about having a really deep clean of that area," she said on Wednesday.
Dr Spurrier said the risk of contracting the virus from luggage was "extremely low" but advised passengers to wipe down their baggage as a precaution.
"There's absolutely no harm in giving your suitcase a wipe particularly around the handle," she said.