*The contents in this blog relates to legislation in New South Wales.

In 1999, the NSW Supreme Court handed down an important decision which extended the duty of care afforded to patients to the patient’s partner in certain circumstances. We explore the case below and what it means for patients.


  • AT was a separated man that had unknowingly contracted HIV during unprotected sexual intercourse with a sex worker.
  • AT first saw the defendant, Dr Oei, in November 1991, and at that time, he complained to Dr Oei that he had a sore throat, fever and cough. Dr Oei made a provisional diagnosis of viral laryngotrachitis and pharyngitis.
  • By the second consultation in January 1992, AT’s symptoms had progressed to include lethargy, abdominal pain and urinary symptoms. During this consultation, Dr Oei arranged a full blood count, liver function test and Hepatitis screen for AT.
  • During a later consultation in February 1992, Dr Oei informed AT that the results for the liver function test had returned and suggested that he had Hepatitis B. Dr Oei then questioned AT as to whether he had engaged in anal intercourse with another man or intravenous drugs use, both of which AT denied. Dr Oei then provided AT with pamphlets, two of which concerned Hepatitis B, and one concerning safe sex practices.
  • In March 1992, AT commenced a relationship with BT, who he had told about his diagnosis of Hepatitis B.
  • In September 1992, AT and BT commenced living together as de facto partners and by that time were having unprotected sexual intercourse.
  • Until their final consultation in January 1993, AT continued to return to Dr Oei with his reoccurring symptoms. Within these consultations, Dr Oei had arranged further tests for AT; however, he did not arrange a HIV antibody test.
  • In February 1993, BT became ill and began seeing a doctor about her symptoms.
  • In February 1994, BT returned to her doctor due to her ongoing symptoms and her doctor arranged for a HIV antibody test which returned positive.
  • In October 1994, AT’s liver specialist arranged for him to undergo a HIV test which also returned positive.
  • In February 1995, AT was admitted to hospital for a liver transplant where he died of liver failure. AT’s death was not a consequence of HIV or AIDS.
  • On 24 February 1995, BT commenced proceedings on her own behalf and on behalf of the estate of AT. BT sought damages for personal injuries arising out of Dr Oei’s alleged negligent failure to diagnose AT’s HIV illness and to counsel him (adequately or at all) to undergo an HIV antibody test.

What did the Court decide?

Justice Bell held that Dr Oei did owe BT a duty of care. In coming to this decision, she considered cases from other jurisdictions including Canada which had found a duty of care existed in similar circumstances. Justice Bell said:

  • There is no conflict between the duty owed by the defendant to AT and BT as the two are coincident;
  • BT was a sexual partner of AT;
  • It was reasonably foreseeable that AT, if HIV positive, would transmit the virus to a sexual partner;
  • AT was unaware of his HIV status (in this respect the condition was latent);
  • The defendant’s specialist knowledge and training equipped him to identify the risk that AT had contracted HIV;
  • Failure to diagnose and adequately counsel AT to undertake an HIV antibody test exposed AT’s sexual partner/s to the real risk of contracting a fatal disease.

Ultimately, Justice Bell found in that Dr Oei had breached his duty of care to AT, and by extension BT, as at 1 December 1992 when AT returned to Dr Oei’s rooms that a general practitioner exercising ordinary care and skill given AT’s history would have considered a diagnosis of HIV and counselled AT as to the need for an HIV antibody test.

What does this mean for patients?

The decision extends a duty of care owed by a doctor to their patient to the patient’s partner in limited but extremely important scenarios.

Get in touch

If you are concerned about any medical treatment, get in touch with us on 13 43 63.

We have specialist medical negligence lawyers throughout NSW who will assess your case and provide personalised advice regarding your legal entitlements. Our medical negligence lawyers are located across NSW including in our offices in ParramattaSydneyWollongongNewcastle and Toronto.


This blog has been written with the assistance of Josie Southern, paralegal.