Allrounder Cameron Green and coach Andrew McDonald are the latest members of Australia's squad to test positive to COVID-19.
Batter Travis Head contracted the virus after the first Test against West Indies in Adelaide but tested negative on Tuesday after flying to Brisbane on his own ahead of the second match of the series at the Gabba.
Head joined the squad for training on Wednesday afternoon and is free to take part in the Test that starts on Thursday without any restrictions.
In line with Cricket Australia protocols, Green and McDonald will be able to play their part in the Test even if they do not return negative results in the next 24 hours.
There is a dedicated change room at the Gabba which has been used in the past when COVID was at its prime. When the duo are sitting in and around open areas they will be separated from the group, until they return a negative test.
The Australians have a business-as-usual approach to the health hiccups with opener Steve Smith adamant Green will fulfil his normal role.
"He is fine. There is no physical drama at all. He's just tested positive (but) him and Andrew McDonald are fine," Smith said.
Smith quipped that it could be "a lonely week" for Green but said his ailment would not impact the slip cordon in the field.
"Greeny is in the gully anyway so he is away from us," Smith joked.
Australia lead the two-Test series 1-0 after winning the first match in Adelaide by 10 wickets.
The Test at the Gabba is a day-night affair with Australia captain Pat Cummins saying the hosts' familiarity with utilising the pink ball could work to their advantage.
"No doubt playing a pink-ball Test almost every year and some Shield cricket over the years with the pink ball helps us familiarise ourselves ... perhaps better than oppositions can, just by experience," he said.
