The walkout involves more than 7,000 nurses at Montefiore Medical Center in the Bronx and Mount Sinai Hospital in Manhattan, the New York State Nurses Association said in a statement.
The COVID-19 pandemic along with a respiratory syncytial virus outbreak and this year's flu season has put a strain on the healthcare sector across the nation's most populous city, creating tensions between nurses and their employers.
Hundreds of striking nurses Monday rallied outside of both hospitals where they chanted "Every patient is a VIP" as they waved signs in support of hiring more nurses and better pay.