Nurses fighting COVID-19 in the frontline are suffering burn-out or psychological distress.
The International Council of Nurses said many have faced abuse or discrimination outside of work.
Supplies of personal protective equipment for nurses and other health workers in some care homes remain insufficient, it said, marking World Mental Health Day on Saturday.
Here's ICN's chief executive Howard Catton:
"We are extremely concerned about the mental health impacts on nurses. Our most recent survey of national nursing associations showed that more than 70 percent of them were saying that nurses have been subject to violence or discrimination."
The figure was based on responses from roughly a quarter of its national nurses' associations in more than 130 countries.
Catton added that nurses face a broad spectrum of issues that affect their mental health, including physical and verbal abuse.
"There are nurses who have been subject to discrimination, where their landlord has not renewed their lease for their apartment, or they can't get childcare for their children."
ICN has lobbied for better protection and working conditions for nurses on the front lines of the pandemic.
But Catton added that some care homes and long-term care facilities in Europe, and in North and South America still lack supplies, citing its members' survey.