Italian Prime Minister Giuseppe Conte put the entire country into lockdown on Monday, banning all but the most important cross-border travel. Lombardy is expected to remain under quarantine until at least April 3.
"I was lucky I left when I did but everyone is stressing, even my new host mum keeps saying 'don't leave the house, don't go into Italy'," she told AAP on Tuesday.
"Everyone is very scared, especially for their older parents."
Ms Turnbull, who subsequently worked as an au pair in Switzerland, said many of her friends were stuck in Italy or had already left.
Her host family became anxious after she returned from a trip to Venice on February 25 as coronavirus spread dramatically trough Italy.
"The family was so scared they made me stay in my room. I couldn't even hug the kids goodbye when I left," Ms Turnbull said.
"It all just hit me like a tonne of bricks, it was like the world is ending."
Ms Turnbull is due to arrive home in Brisbane on Wednesday night after booking flights on Sunday.
AAP