A spike in sick leave among paramedics reduced the number of ambulance crews operating across Victoria overnight, according to the union.
At least 50 crews were taken off state roads, with crews dropped from metropolitan and rural areas.
The Victorian Ambulance Union said members reported crews had to drive more than 60km to reach Code 1 cases, which are considered high-priority and time-critical incidents.
About 20 crews were dropped from rural areas including Hamilton, Barwon Heads, Norlane, Warrnambool, Swan Hill, Heathcote, Bendigo and Mildura.
Meanwhile, at least 30 were dropped in Melbourne, including Bayswater, Brighton, Sunshine, Doncaster, Rowville, Mordialloc, Hartwell, North Melbourne and Oak Park.
“The members rarely get breaks, almost never finish on time and they are exhausted and burnt out. So, this is the reality we are facing,” Victorian Ambulance Union secretary Danny Hill said.
“We have been warning about the need to better support the workforce, so we have a healthy and well supported workforce.
“If you don’t support the workforce, then the response to the community suffers”.
There are normally 120 ambulances working night shifts each night. Last night only 90 were in action, according to the union.
Ambulance Victoria said it had “as many crews on the road as possible” as illnesses hit the workforce.
“The health system is extremely busy due to seasonal illness (circulating) within our communities and our workforce, and we acknowledge the workload of our paramedics right across the state,” a spokesperson said.
“We have as many crews on the road as possible and our priority will always be responding to the sickest and most time-critical patients.
“We use a dynamic operating model that relocates resources as necessary to minimise rostering impacts.”