More than half of the 300 people in intensive care units in France with the new virus are under 60.
The head of the national health agency, Jerome Salomon, announced the statistic Saturday night as France saw another jump in new virus cases.
For most people, the virus causes only mild or moderate symptoms, such as fever and cough. For some, especially older adults and people with existing health problems, it can cause more severe illness, including pneumonia. Of the 91 people who have died in France, 71 were over 75, Salomon said.
No details were immediately available about the patients under 60 in intensive care.
France now has confirmed 4,500 cases since January. Salomon stressed that 98% of patients survive, but he called for mobilization to help the most vulnerable.
To stem the spread, the French prime minister ordered all restaurants, cinemas and nonessential stores closed starting Sunday, a dramatic move for a country whose economy depends heavily on its global reputation for cuisine, culture and fashion.