Contact tracing is usually carried out by the treating medical practitioner who decides with their patient how to inform contacts. If a person refuses to tell their sexual contacts and refuses to consent for their healthcare worker to do so, the Public Health Act 1997 (ACT) (s 108) states the healthcare worker may inform the chief health officer who may take reasonable steps to ensure that the contact is informed of their potential exposure to HIV. The chief health officer may delegate that responsibility to a medical practitioner, nurse practitioner, or suitably qualified and experienced counsellor. The Act also states (s 106) that an authorised officer may request an HIV-positive person to provide information about the circumstances under which the person may have acquired or transmitted the condition, as well as the names and contact details of persons believed to be a contact of the HIV-positive person.