More than 150 staff at prisons around the country are currently on paid special leave after refusing to get vaccinated.
Those 152 represent just 3.5 per cent of all prison-based staff, including Corrections officers and accounts, who opted against having their first vaccine by the mandated November 7 deadline.
They now have until December 8 to get fully vaccinated or they will have their positions terminated.
Rimutaka Prison in Upper Hutt, as of Thursday, had the highest number of staff - 24 or about 5 per cent - who had refused the vaccination. This is followed closely by Spring Hill Corrections Facility, which has about 4 per cent or 15 staff who have not even had their first jab.
But Department of Corrections regional commissioner Terry Buffery said the vast majority of prison-based staff were vaccinated and therefore placing those on leave had not had a significant impact on staff levels.
Buffery said losing 15 of 486 or just under 4 per cent of prison-based staff at Spring Hill had also not had any major impact on unlock hours or any other material impact on the operation of the prisons.
Since March 2020, Corrections said it had put in place extensive plans to manage the risk of Covid-19 including how to safely operate at reduced staffing levels if significant numbers of staff became unwell or needed to isolate.
However, Corrections Association president Floyd du Plessis said having about 150 staff on leave had definitely put pressure on the remaining staff especially at Spring Hill Corrections Facility and the Northland Regional Corrections Facility in Kaikohe where higher numbers had refused the vaccine.
"It hasn't resulted in a major event of any kind as yet, but it is putting pressure on the staff at this stage as we go through it."
On October 20, the Government extended its Covid-19 vaccine mandate to include people working in prisons across the country and giving them until midnight November 6 to have their first dose.
Du Plessis said the short-notice given to staff about the vaccine mandate was one of the major reasons for reluctance as staff hadn't been given enough time to process and listen to the information out there.
While some couldn't get vaccinated because of medical reasons, some simply didn't want to and some wanted more information before making the decision, he said.
However, du Plessis was confident more of its members would get the vaccine and already more than 50 people had got the jab since Sunday.
"Some of them have purely got it out of coercion and the fact that if you don't get it you will lose your income, which is unfortunate."
He said the association would hate to lose any one of their members who did an amazing job because of the mandate.
When announcing the mandate last month, Department of Corrections' national commissioner Rachel Leota said many of those in prison were most vulnerable to Covid-19 because of the transmission that could occur in residential facilities with large numbers of people living in close proximity.
She acknowledged the short-time frame which gave staff just 17 days to get their first vaccine and required them to be fully vaccinated by December 8, but said more than 80 per cent of their frontline staff had received their first dose as of October 11 and more than 65 per cent were fully vaccinated.
In May, Corrections launched a vaccination programme to encourage staff to get the jab.
National's Corrections spokesman Simeon Brown said he wanted to see Corrections work with staff who were hesitant but the reality was they were given very little time to get their first dose compared to doctors, nurses and teachers.
He hoped Corrections would continue to engage with staff to get them back on the floor.