Victoria has recorded 80 new local Covid-19 cases — the highest jump in daily infections seen during the current outbreak.
Continuing a concerning trend, the source of 13 new cases is currently a mystery, following nine mystery infections on Wednesday.
Victoria Health said 41 of the 80 cases were out in the community while infectious.
The total number of active cases in the state is 600, the majority of which are people aged between 20 to 39.
Covid outbreak causing distress in regional Victoria
The Delta outbreak has hit Victoria's health system hard and is causing distress in the regional town of Shepparton.
The state's exposure sites list has ballooned past 800, including the emergency department of Monash Medical Centre which is now listed as a tier one exposure site.
Victoria is recruiting 350 overseas doctors and nurses to ease pressure on a hospital system facing hundreds of workers being furloughed due to coronavirus exposure, including at Royal Melbourne Hospital and Goulburn Valley Health.
The Goulburn Valley is battling an outbreak centred in Shepparton with at least 50 cases and 17,000 residents in isolation.
Among those told to quarantine are supermarket staff, prompting many shops to close for cleaning, limiting access to essential supplies.
Meanwhile, more than 95,000 Victorians booked vaccine appointments at state-run hubs to 4pm on Wednesday, despite the online system being overwhelmed as Pfizer eligibility expanded to those aged 16 to 39.
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