The driver is in quarantine in South Australia, and his co-driver who travelled alongside him has tested negative.
Although he was likely infectious the entire time he was in the state, authorities say the risk of transmission is low.
Health authorities are currently working to identify any close or casual contacts, as well as any exposure sites.
Currently, four service stations in Balcatta, Kewdale, Balladonia, and Norseman have been listed as potential exposure sites.
For more details on the exposure sites, visit that Healthy WA website.
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