An extra 80 hospital beds will be opened across Adelaide's hospital network along a new acute assessment centre as part of a winter strategy to deal with the ongoing COVID-19 pandemic and a rise in flu infections.

The extra beds are on top of the 180 opened in the past few weeks after the new Labor government took what it called urgent action to strengthen the hospital network.

The winter strategy also includes more resources for virtual and community care along with a program of free flu vaccinations.

It comes as flu cases continue to rise after the release of ambulance ramping figures which showed 3412 hours were lost in May.

COVID-19 infections appear to have stabilised but daily case numbers have remained persistently above 2000 in recent days, with more than 200 people in hospital.

"This is the first winter since the pandemic hit that our health system will be required to manage both COVID-19 and the flu, as well as normal winter demand, and we know this will be a challenge," Health Minister Chris Picton said.

"This is the state's first winter demand strategy in four years and does everything we can with the situation we have inherited to generate more capacity."

As part of the winter strategy, the acute assessment centre at the Royal Adelaide Hospital will allow patients who need to be admitted to bypass the emergency department.

The government is also working with private hospitals and day surgeries to perform more elective surgery procedures.