Contact tracing

Contact tracing or partner notification is the process of identifying relevant contacts of a person identified with an infectious disease so they can be informed about their exposure and be offered physical examination, investigations and treatment. Contact tracing is an essential part of the clinical management of patients diagnosed with STIs and blood-borne infections.

Health care providers have a professional responsibility to ensure contact tracing takes place. In most cases contact tracing can be undertaken by the index case with assistance from health care providers as required.

When performed well, contact tracing supports sexual health education,and is an opportunity to provide individual interventions that bring about sustained behaviour change e.g safer sex/injecting, alcohol and other drugs

Contact tracing definitions


A person who has had sex with, shared injecting equipment with, or has had some other high-risk exposure to the index case.

Sexual contact

Contact may be oral, vaginal, anal or some other form of sexual contact e.g. sharing sex toys/implements with the index case during the period when there was risk of transmission of infection.

Index case

The original person identified with an infection. The index case may or may not have infected other persons but represents a starting point for the process of contact tracing.

Contact tracing or partner notification

Contact tracing or partner notification is the process of identifying relevant contacts of a person identified with an infectious disease so they can be informed about their exposure and be offered physical examination, investigations and treatment.

General principles
  • Contact tracing is an essential part of STI/BBV management.
  • Health care providers have a professional responsibility for ensuring that reasonable efforts are made to identify relevant contacts so they can be informed about their exposure and be offered physical examination, investigations and treatment.
  • Health care providers should respect the human rights and dignity of the index case and the identified contacts.
  • All aspects of contact tracing must are confidential, including written and database records. The anonymity of the index case must be protected unless written permission has been given to release this information to contacts.
  • Contact tracing should be voluntary and without coercion. Consider the reasons why the index case is not disclosing contacts, for example intimate partner violence.
  • Specialist advice about, and assistance to undertake, contact tracing may be sought from the local Population Health Unit (Healthy WA)
Identifying contacts

When taking history to identify contacts:

  • explain the reasons for needing to identify contacts and reassure the patient about the confidentiality of the information
  • ask open-ended questions and use appropriate level of language, i.e. use the words your patient uses
  • do not presume the gender of contacts – ask about male and female contacts, use gender neutral pronouns and be non-judgemental
  • ask explicit information about behaviours which are associated with STI or BBV transmission risk.
  • ask where they may have acquired the infection e.g. overseas
  • ask where/how they meet their contacts e.g internet, mobile phone apps, sex on premises venue
  • look for indicators of intimate partner violence. If you suspect, consider screening for intimate partner violence. Refer to Intimate Partner Violence and STIs section for more information
  • ask about substance use that may have contributed to risk
  • if necessary, reinterview at least once more
  • attempt to get further information about contacts, e.g. email or mobile telephone numbers may help.
  • Offer assistance in contact tracing if appropriate.

To assist index cases to remember contacts, ask about events of significance (e.g. birthdays, anniversaries, travel, holidays, mardi gras, sporting carnivals), and then specifically about sexual encounters at the time of each event.

Refer to the infection’s incubation period and the index case’s clinical history to determine the appropriate time frame for identifying contacts. It may be useful to start with the most recent contact and work backwards in time to ensure that all relevant contacts, not just the most recent, are identified.

Choosing a method for contact tracing

There are different methods by which contacts can be informed by the index case themselves or a health care provider:
  • In person
  • Mobile or home telephone
  • SMS
  • Social Media
  • Email
  • Letter
  • Referral to a specialist agency
Online resources available to support both patients and health care providers to undertake partner notification include:

Patient (index case) referral

The index case personally notifies his or her contacts. This requires specific instructions including advice on which contacts to inform and what information to be communicated, including appropriate agencies for assessment and counselling. Patient referral is recommended for well-informed, motivated and confident index cases. Discussion of various scenarios and how they can inform contacts may be helpful. If the index case fears embarrassment or reprisal from contacts e.g. intimate partner violence (IPV), seek assistance from the public health unit (Healthy WA) to undertake contact tracing in a way that minimizes risk to the index case’s safety. For further guidance on how to support a patient who may be at risk of IPV, see section Intimate Partner Violence and STIs. It is important to use follow-up consultations to confirm that the contacts have been notified and assessed adequately.

A sample letter (PDF 16KB) for your patient's contact to pass on to their own GP is provided. The letter explains:
  • that they have been in contact with a person diagnosed with an STI/BBV and may have contracted an STI/BBV
  • the importance and need for examination and testing, and empirical treatment of chlamydia, gonorrhoea and syphilis.

Provider Referral

Provider referral may be selected either at the index case's request, or at the recommendation of the index case’s health care provider. In such cases the provider may undertake to notify contacts directly, or seek assistance from the local public health unit (Healthy WA). Provider referral requires the explicit approval of, and offers greater anonymity to, the index case.

Approaches to contact tracing by health professionals

Approaches by phone


  • Quick and low cost.
  • Opportunity to provide immediate information to the contact and allay their anxiety.
  • Opportunity for the health care provider to assess immediately the contact’s willingness to participate in contact tracing., allows an appointment to be made immediately.
  • Confidential (provided that the source of the call is only revealed to the contact).


  • Provides only verbal/auditory information.
  • Contact may be uncomfortable disclosing information over the phone to a health care provider they do not know/trust.
  • Confidentiality may be compromised as phone conversions can be intercepted/overheard by other people.
  • Not practical for the hearing impaired.

Approaches by letter


  • Confidentiality can be assured if registered mail is used
  • Cost effective


  • May create anxiety, especially if read when services are closed.
  • Inappropriate for disclosing details.
  • Difficult for people with literacy problems or for the visually impaired.
A sample letter (PDF 16KB) for patients to pass on to contacts is included. The health care provider should consider the appropriateness of using such a letter.

Approaches in person/Home Visit


  • Face to face contact gives the health care provider opportunity to manage the contact’s response s.
  • Opportunity for health care provider to assess the index case’s home/social situation.
  • Depending on the circumstances and the health care provider's training, immediate testing, empirical treatment, support and referral to appropriate services can be offered if appropriate.
  • Informal approaches in small communities can minimise confidentiality risks.


  • Risk to the health care provider, especially if undertaking this task by themselves
  • Presence of a health care provider with the index case outside a clinic setting can be sufficient to breach the index case’s confidentiality and negatively influence their willingness to participate in contact tracing.
  • Human resource and time intensive.

Referral to another agency

For common bacterial STIs such as chlamydia and gonorrhoea, it is preferable that the index case’s contacts be identified, examined, tested, counselled and treated by the health care provider or clinic that treated the index case. However, structural, geographical or other factors may make it necessary for contacts to be referred to a public health unit (Healthy WA) or specialist sexual health service.


  • Opportunity for the index case’s health care provider to limit their involvement to that of their patient, i.e. the index case.
  • Opportunity to access to specialist knowledge of contact tracing and public health management.
  • Allows the index case’s confidentiality to be maintained if information that could identify them is not included in the referral.


  • Break in continuity of care.
  • Complication of involving another party.
  • Delay in contact tracing.
  • Perception of breach in confidentiality.
Empirical treatment

A strategy that is effective in reducing the prevalence of infections within a community is empirical treatment. This is where the contact of a proven case of gonorrhoea, chlamydia, trichomoniasis or non-specific urethritis (NSU) is treated on the day they are interviewed and investigated, rather than waiting until the results are back. Treatment should be offered regardless of whether the contact is symptomatic or not.

Rationale for empirical treatment:

  • these infections are highly infectious so there is a high probability that the contacts are infected
  • the contact interview may be the only opportunity there is for treatment if considered to be in a high risk group e.g. itinerant, homeless, has mental health issues, drug and alcohol use
  • the earlier treatment is initiated reduces the risk of reinfection and may reduce complications and further transmission in the community.

If GeneXpert point-of-care test is available, contacts can be treated on the basis of their point-of-care test result.

Syphilis testing and treatment can be more complicated, ideally serology results should be reviewed before treatment is commenced for asymptomatic contacts of syphilis. However, persons who were sexually exposed to a index case with infectious syphilis (primary, secondary, or early latent) should be tested and treated presumptively. If in doubt, offer the contact empirical treatment, (e.g. Benzathine penicillin 1.8 g intramuscularly as a single dose) especially if there is potential for onward transmission if the contact is infected.


Follow-up with the index case for contact tracing is essential to ensure that all possible contacts have been identified and informed . If none of the named contacts were found to have the same infection as the index case, it is important to reinterview the index case and maybe extend the time frame of the sexual contact history further back in time.

If the primary health care provider is not in a position to ensure that identified contacts are traced and receive screening and treatment, contact tracing support may be obtained from the local public health unit (Healthy WA).

Urgency of contact tracing

The concept and importance of contact tracing should be discussed with the index case at the initial interview/presentation, especially if they have symptoms and/or clinical signs of STIs/BBVs.

Urgent (or immediate) contact tracing is necessary when there is concern that a contact is placing others at immediate risk of infection and for antibiotic resistant organisms such as penicillin-resistant Neisseria gonorrhoeae.

Rationale: The longer that contact tracing is delayed, the greater the likelihood of an infected contact transmitting the infection to other individuals (or re-infecting the index case). While it is accepted practice to await confirmation of the infection before starting contact tracing, this should be reconsidered for rural and remote areas, where laboratory results may not be received for a week. There is a risk that, after a week, it will be more difficult to locate and treat the contact quickly. Delays in treating contacts are considerably reduced if contact tracing is begun when the index case first presents.

Special considerations

  • If the index case is acutely physically ill or emotionally distressed, it may be better to defer the issue until a subsequent consultation, provided that the index case can be relied upon to return.
  • For many index cases, the issue of notifying contacts will have a high priority and the provider should assist them to deal with the issue immediately.
  • For common, readily treatable bacterial infections (e.g. chlamydia, gonorrhoea and syphilis), contact tracing is usually  discussed during the initial visit. For chronic viral STIs/BBVs, particularly HIV, which are less infectious, contact tracing is less urgent may be deferred to a later consultation after the patient has had time to consider the implications of their chronic infection.
  • Contact tracing of index cases with penicillin-resistant gonorrhoea is a matter of public health urgency to prevent such strains from being transmitted locally and becoming established in WA.
Uncooperative index cases/contacts

Advise the local Public Health Unit's (PHUs) (Healthy WA) directly and confidentially of non-compliant individuals, particularly in the case of penicillin-resistant gonorrhoea, and serious infections such as syphilis and HIV.

A strategy for a short-term management plan should be agreed between the primary health care provider and the PHU.

Rationale: Infectious diseases legislation places control of communicable diseases under the management of PHUs. However, this is a last resort, when counselling by the primary health care provider has been unsuccessful in persuading the index case to comply with contact tracing and treatment protocols.

Problems and possible solutions for patients reluctant to cooperate.

It is helpful to understand why the index case/contact is reluctant to cooperate. Possible reasons and options for addressing them include:
  • Fear of loss of confidentiality: Offer provider referral for greater anonymity.
  • Index case unwilling to inform contacts: Practise role playing (perhaps with counsellor assistance). Offer anonymous online sites e.g Let Them Know (external site)
  • Patient not reconciled to diagnosis: Allow more time and support if contact tracing is not urgent. This option is not appropriate for cases of gonorrhoea and infectious syphilis due to their high infectivity and potential to cause serious complications including congenital infection.
  • Unaware of seriousness of consequences: Provide appropriate education materials and discuss.
  • Little concern for consequences to contacts: Emphasise serious consequences that the index case can relate to, e.g. infertility, congenital infection. Explain that contacts tend to find out eventually; emphasise the risk to the index case of re-infection from untreated contacts and any legal requirements.
  • Socio-cultural or language differences between the health care provider and the index case: Seek the assistance of a culturally appropriate agency or professional interpreter.
  • Fear of reprisal from partner/s: Explain disease process. Encourage and provide support. Discuss various scenarios and how they can be dealt with and also offer to inform the contact. If client in fear of violence from (ex) partner, discuss safety planning PRIOR to notifying contact(s). For further guidance see section Intimate Partner Violence and STIs.
  • Shame of having an infection: Explain disease process.

Online resources

Providers can improve their skills using the WA or ASHM partner notification (contact tracing) modules online. The modules are designed for nurses and Aboriginal Health Workers in WA. View the WA partner notification (contact tracing) modules on the Australian Society for HIV Medicine website (external site)

FREE online learning program (external site) funded by the Department of Health Western Australia with the primary aim of increasing the knowledge and skills in managing sexually transmitted infections through the education of medical practitioners, nurses and other professionals in Western Australia. It has been allocated CPD hours according to the Nursing and Midwifery Board of Australia - Continuing Professional Development Standard.

Training in STIs and contact tracing is available via The Short Course in Sexual Health Nursing Online Modules (external site) hosted by the Australian Society for HIV Medicine website (external site). The online training provides knowledge and skills in managing sexually transmitted infections and is for medical practitioners, nurses and other professionals in Western Australia. It has been allocated CPD hours according to the Nursing and Midwifery Board of Australia - Continuing Professional Development Standard.