The protestors, some who are employees of the healthcare system and some who aren't, said they're fighting for medical liberty, but the hospital says the decision is about safety.
"We all have the right to the freedom of our bodies and what we put in our bodies," said Adriana Brown, a protestor who does not work at the hospital.
Protestor Helen Ruan said, "What I'm thinking, Americans have to stand up, this is not a country like the CCP (Chinese Communist Party) controlled by a tyrant and dictatorship."
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Last month, ChristianaCare joined nearly 100 health care systems across the country in mandating the COVID-19 vaccine for all employees.
"The imminent danger posed by the highly transmissible delta variant of COVID has tipped the scales in our effort to balance the right to personal freedom with the right to having a safe workplace," said Dr. Ken Silverstein, the chief physician executive of ChristianaCare.
"We are not standing here as an anti-vax. We are standing here against the mandate. No forced compliance to get the vaccine in order to keep your job," said Tori Malin, who organized the protest.
She is a former patient care tech with the hospital.
She says she put in her two-week notice earlier this week in response to the mandate but was told to leave that day.
"I kind of would have the power to take that power back from Christiana and leave on my own terms instead of being terminated. For me, this was the hill I was prepared to die on," she said.
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The hospital says the vaccine is saving lives.
"COVID has shown more clearly than ever how we are all interconnected. Vaccination is the best way to protect each other," said Silverstein.
The hospital is giving employees six more weeks to comply with the mandate. They have until September 21 to get their first shots.