WA Health officials are continuing to investigate how a returned traveller has contracted COVID-19 from an infected guest while staying at the Pan Pacific Perth.
The WA Health Department reported the case after genome testing linked the two guests, who were staying in adjacent rooms.
It's understood Pan Pacific had advised WA Health that all rooms were negative pressure, a function which helps prevent airborne transmission.
WA Chief Health Officer Dr Andrew Robertson said the cases remain in quarantine and have been moved to alternate rooms.
“We are still exploring the best options for their management.” he said.
12 other guests who were staying on the same floor tested negative on Day 13 but will continue to be monitored.
It’s the second case of a quarantine breech at the Pan Pacific Perth Hotel in the past month.
The cause of the latest transmission is not yet known.