The NHS has offered to conduct HIV tests on 400 patients who were reportedly operated on by a HIV positive surgeon.
Emergency clinics are being set up, despite doctors believing the chances of any patients being infected are "very low".
The surgeries were conducted between June 2010 and February 2015 by an unnamed locum medic was working in orthodpaedic surgery and A&E at three NHS hospital trusts. It was not known that he was HIV positive at the time.
A total of 223 patients who were operated on by surgeon at Queen's Medical Centre and Nottingham City Hospital, both run by Nottingham University Hospitals NHS Trust, have been recalled for blood tests.
Another 120 patients at Chesterfield Royal Hospital NHS Foundation Trust and 57 patients at Royal Cornwall Hospitals NHS Trust have also been contacted.
The trusts are setting up emergency clinics to conduct the tests. Dr Stephen Fowlie, the medical director at the Nottingham hospital, told The Telegraph that the contacted patients would be promised a 24-hour turn-around on their blood tests.
He explained that the human immunodeficiency virus can be transmitted from a HIV positive healthcare worker to "a patient with an open wound" only if the health worker has an injury with bleeding while are operating on the patients.
"There is no evidence this happened to this doctor in any patient contact," Fowlie said.
Dr David Levey, regional medical director for NHS England Midlands and East, also said "clinical evidence shows that the risk of infection is extremely low and it is highly unlikely that any of the patients being contacted will have been infected with HIV.
"Advice and counselling is available for those affected by this recall, and we could encourage them to access this support. It is our first priority to identify and provide reassurance to the individuals being contacted at this time," Levey added.
The surgeon is reportedly not working with any NHS hospitals anymore.