More than a quarter of care home staff in Bedford have not been vaccinated against Covid-19.
Unison, which represents care workers, said employees should be encouraged, not intimidated, into receiving a jab and added that those who are uncertain needed support.
NHS data shows 1,633 workers in care homes for older adults in Bedford were eligible for a first dose of a vaccination up to March 7, but just 1,195 received it.
It means 27 per cent of staff, including agency workers, have not had a jab.
Across England, the uptake rate varies by region with the North East and Yorkshire having the lowest proportion of unvaccinated staff – 22 per cent.
By contrast, 40 per cent of care home staff in London have not had their first jab.
Staff members and residents in care homes for older adults are in the top four priority groups for the vaccination.
Last month, Prime Minister Boris Johnson said everyone in those groups - which also includes people aged 75 and over and those clinically extremely vulnerable - had been offered a first dose.
Since then, a growing number of care home providers have made it a requirement for new staff to have the Covid-19 vaccine.
But Unison said such a "heavy-handed approach" is the opposite of what is needed to encourage workers to have the vaccine.
Gavin Edwards, the union's national officer for social care, said: "Everyone who can have a jab should, including social care staff, but some employers are intimidating their employees which leads to a lack of trust in the vaccine."
He added: "Staff who are hesitant need support, accurate information and the chance to talk about their concerns.
"Care employees work long shifts, antisocial hours and at different sites. Vaccinations need to be offered at a convenient time and place for workers."
Chief medical officer for England, Professor Chris Whitty, said healthcare staff had a "professional responsibility" to get vaccinated.
There are no clear signs yet that the Government will make it compulsory.
A Department of Health and Social Care spokesperson said: "We have visited every eligible care home in England, offered vaccines to all staff, and are doing everything we can to ensure all those who can, take up the vital offer.
"All eligible staff can book using the national booking service.
“We continue to work closely with the care sector and local leaders in communities with lower take up to maximise vaccination numbers and save thousands of lives.”
In Bedford, 877 residents in care homes for older people have received their first dose of a vaccination – equating to 91 per cent of eligible residents.