French patient is first to be infected with Aids by doctor

A woman in France became infected with the Aids virus after being operated on by a surgeon in what is believed to be the first documented case of doctor to patient transmission.

The woman, one of 3,000 operated on by the surgeon who did not know for 10 years that he was HIV positive, is only the second case worldwide in which a healthcare worker is thought to have transmitted HIV to a patient. A dentist in Florida was blamed for infecting five of his patients during the late 1980s.

In France, where the details of the case have just emerged, it has prompted an overhaul of procedures in the health service following what are known as "professional accidents".

The surgeon, Dr Patrick Cohen, had operated on the woman twice between 1992 and 1993. During the second, lengthy and difficult operation, he had pierced his gloves and injured his hands. His blood is thought to have contaminated the patient through her open wounds.

Dr Cohen, an orthopaedic and trauma specialist, believes he became infected with HIV in 1983 after operating on a woman who had received several blood transfusions. He was unaware of his HIV status until his health failed and he was diagnosed with Aids in 1993.

In 1995 he wrote to the French ministry of health asking that his former patients, about 3,000 people, be traced and offered HIV antibody tests. A total of 968 patients who were contacted agreed to have the tests and one was found to be HIV-positive.

According to a report in tomorrow's issue of the British Medical Journal, the woman was known to have received a blood transfusion at the time of her operations from two donors, both of whom had tested, and continue to test, HIV-negative.

Professor Luc Montaigner, the man who first identified HIV in 1984, was asked to analyse HIV taken from the woman and from Dr Cohen. He concluded that the two viruses were very similar and that "a great probability existed that HIV transmission occurred between two patients".

Professor Montaigner described the incident as exceptional, pointing out that Dr Cohen's blood would have been highly infectious, as he had acquired the virus nine or 10 years previously, had never received treatment and was progressing towards full-blown Aids at the time of the operation, when transmission occurred. He recommended that healthcare staff be encouraged to report professional accidents; that surgeons should be tested following any injury which could result in the transmission of HIV, and that HIV- positive staff surgeons should not perform invasive or complex procedures on their patients.

An American study of 22,000 patients treated by HIV-positive staff did not find a single case of transmission of the virus.

A number of doubts have lingered about the the case of the Florida dentist, David Acer, and how transmission to five of his patients actually occurred in that case.

There are a number of cases in which staff have been infected by HIV- positive patients through needlestick injuries or other routes of exposure.