Queenslanders are being asked to wear masks in some settings to counter a fourth COVID wave. There’s been a 15 per cent increase in active cases in the past week and a doubling in the number of COVID patients in hospitals. The rise has prompted a switch in the state's COVID traffic light advisory system from green to amber. Queenslanders are being advised to wear a mask when in healthcare settings, on public transport, indoors where social distancing isn't possible, and when around vulnerable people.