Plans to open up £1.2bn of NHS services to competition - including ulcer and wound care and continence services - could cause long-term uncertainty for nurses.
The government said last week its plan for patients to choose from “any qualified provider” would be brought in more slowly, following the “pause” in the NHS reforms.
However, managers across the country have been told to begin opening up eight community and mental health services - including those for back and neck pain, wheelchairs for children and talking therapies - from next year.
The Department of Health said the plan was “designed to make services more responsive to patient choice”.
It said locally or nationally set prices for services would prevent providers from undercutting the NHS and that making services “contestable” would improve efficiency.
Unison head of health Christina McAnea said the plan “leaves the door wide open for privatisation” and would make patients “little more than consumers”.
Private firms or charities delivering the services would be regulated by the Care Quality Commission and Monitor. Neither companies nor the NHS would be guaranteed income or activity, which will be determined by patients’ choices.
Unison warned nurses would face “long-term instability and uncertainty”, with organisations struggling to survive. Staff employed by private providers would have worse pay and conditions and their jobs will be at risk if firms collapsed, it said.