Geneva University Hospitals (HUG) said the number of coronavirus patients was expected to be “far higher” than at the peak of the pandemic's first wave in March.
Switzerland's second-biggest city is home to many international institutions including the United Nations.
According to the latest figures released Friday by the Swiss health ministry, 5,057 new cases of the respiratory disease were registered in Geneva over the previous 14 days — an incidence of 1,012.5 per 100,000 people.
Cases, hospitalisations and deaths in Switzerland have doubled from one week to the next throughout October.
The government is expected to decide Wednesday on new measures to control the spread of the virus.
“Faced with the rapid and continuous increase in the number of hospitalisations of Covid-19-positive patients, HUG are looking for voluntary medical, nursing and administrative staff to strengthen and relieve their teams,” the group said in a statement.
They are also calling on recently retired employees or those on unpaid leave to come forward.
“It is highly likely that the peak of 550 hospitalised Covid-positive patients that we recorded during the first wave will be greatly exceeded in the coming days,” said HUG director-general Bertrand Levrat.
“We anticipate that the number of beds and professionals needed to treat Covid and non-Covid patients will be far higher than what we experienced this spring.”
There are currently 296 coronavirus patients in Geneva hospitals — almost treble the number 10 days ago.
In March, during the first wave of infections, Switzerland was not hit as hard by Covid-19 deaths and did not impose as strict a lockdown as some other European states.
From nearly no new cases at the beginning of June, infections rose slowly but steadily before rocketing in October.
On Friday, 6,592 new cases were announced in the daily Swiss update, taking the total throughout the pandemic over the 100,000 mark to 103,323.
Switzerland — population 8.5 million — has so far recorded 1,876 deaths from the coronavirus.