Image copyright Reuters Image caption Prisoners in California can’t be vaccinated without a state or federal authorisation.
A federal judge has blocked a new California law forcing inmates to receive immunisations.
A coalition of health clinics argued that allowing unvaccinated inmates to transmit diseases to other inmates and staff would make public health vulnerable.
But in her ruling on Thursday, Judge Christina Snyder said “the state has failed to show that this mandatory vaccination is necessary to meet the interests it claims”.
The law requires nearly all health professionals to certify that patients have “medical” reasons for refusing immunisations.
Under the bill, hundreds of thousands of Californians must be vaccinated.
California’s prison system now covers some 190,000 inmates.
“Inmates who are healthy but refuse immunizations pose a serious public health risk to the other inmates, the correctional health care staff, and visitors,” said Liz Castro, president of NCLR Health Care Association, in a statement.
“This is a step forward in giving Californians access to a safe and secure correctional healthcare system that protects the public.”
But the California state prison officials called the ruling a “down-sizing decision that undermines public health and medical safety”.
The new law was supposed to take effect on 12 January but has now been stayed pending a March hearing.