Gov. Andrew Cuomo announced Friday that only 57% of hospital workers in the Mid-Hudson have been vaccinated, which is the lowest in the state.

Cuomo says 28% of the region's hospital staff are unwilling to get vaccinated. He says the numbers are troubling.

Experts say at least 70-90% of populations need to be vaccinated to achieve herd immunity.

Some hospitals have vaccinated the most in the Mid-Hudson region. Good Samaritan Hospital in Suffern and New York-Presbyterian Hudson Valley Hospital are almost at 90% and are ranked among the top in the state.

On the flip side, hospitals in the area that have vaccinated the lowest percentage of employees are Catskill Regional Medical Center with 42.7%, Putnam Hospital Center with 43.6% and Vassar Brothers Medical Center with 47.2%.

A spokesperson for Vassar Brothers Medical Center didn't share the hospital's refusal rate or explain why not even half of the staff have been vaccinated. The spokesperson says hundreds of their front-line workers have been vaccinated and they continue to vaccinate them as they receive doses from the state.

Dr. Mark Hirko, president of the Putnam Hospital Center, tells News 12, "We are working daily with staff answering questions regarding their concerns surrounding the vaccine, including complications and efficacy. We are encouraged that more employees are scheduling their appointments for vaccination."

Cuomo says if you are not vaccinating the doctors and nurses, then they will get sick and it will become a super spreader issue.

News 12 reached out to all five of Mid-Hudson's lowest performing hospitals to find out why it's taking so much longer to vaccinate their staff and what their refusal rates are, but has not been able to get clear answers or has not heard back.