Ryan Cho, 28, was arrested on Friday at a property at Croydon in Melbourne's east.
He was interviewed and charged with three counts of producing an intimate image, one of using optical surveillance device and one of failing to comply with a direction to assist.
Cho was charged with other offences, including stalking, a fortnight earlier.
Police allege a phone was found at a restricted toilet for staff inside the Austin Hospital in Melbourne's northeast on July 3.
Investigators believe it was there for "for some time" before workers became aware of the device and reported it to police.
Several other hospitals he worked at in Melbourne and regional Victoria from 2020 to 2025 were identified as "workplaces of interest" by police and put on alert over the allegations.
Police said they had started contacting the additional hospitals and those potentially affected, but warned the process could take some time.
Austin Health chief executive Jodie Geissler said the hospital's focus was on caring for its staff and they have been working closely with Victoria Police to support the investigation.
"This has been an incredibly distressing situation for our staff, and their safety and wellbeing is our absolute priority," Ms Geissler said in a statement.
"We have comprehensive support services in place and are doing everything we can to help them through this challenging time."
On Friday evening, Cho faced court and unsuccessfully applied for bail.
Victoria Police Senior Constable Neral Baykur told the court the majority of the alleged victims appeared to be female doctors, nurses and paramedics, while some videos looked to be in a residential setting.
Victorian Ambulance Union secretary Danny Hill described the allegations as "beyond sickening".
"We owe it to our members to ensure the matter is fully investigated and individuals held accountable," he said.
1800 RESPECT (1800 737 732)
National Sexual Abuse and Redress Support Service 1800 211 028
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