Doctors and nurses across the United States are struggling through a fourth wave of hospitalisations and deaths from COVID-19, driven by the Delta variant and the nearly 40 percent of Americans who remain unvaccinated.

And after more than a year and a half – the pandemic is taking a toll on some healthcare workers who say enough is enough.

Al Jazeera’s Heidi Zhou-Castro has more.

– Follow us on Twitter: https://twitter.com/AJEnglish/

– Find us on Facebook: https://www.facebook.com/aljazeera/

– Check our website: https://www.aljazeera.com/