“University Hospital in Newark is believed to be the first in the state to implement a COVID-19 vaccine booster mandate for employees who got the single-dose Johnson & Johnson shot, according to a hospital representative. “Data and analysis indicate that a single dose of the Johnson & Johnson vaccine may no longer confer a level of effectiveness that prevents COVID-19 infection in enough of our employees if they are exposed, which has implications on our ability to keep vulnerable patients and families safe,” President and CEO of the hospital Dr. Shereef Elnahal said in a statement.”

https://www.newsobserver.com/news/nation-world/national/article255384931.html