Chapter 13 | Sexually transmissible infections and blood borne viruses

• Identify and implement opportunities to make STI and BBV testing routine, including relevant staff training, clinical prompts in medical software, continuous quality activity cycles and the availability of decision-making tools.
• Support periodic clinical audits to ensure clients with hepatitis B and C are monitored and treated.
• Ensure understanding regarding notification and contact tracing protocols, including timely involvement of local public health units.
• Undertake and encourage s100 training to improve access to hepatitis B and HIV prescribing.
• Seek opportunities to build confidence in hepatitis C prescribing through training and relationships with relevant local specialists.
• Make condoms freely and discreetly available, and work with local stakeholders to ensure needle and syringe program (NSP) access.

Clinical guidelines

• Australasian Society for HIV, Viral Hepatitis and Sexual Health Medicine (ASHM): Australian STI management guidelines for use in primary care 
• ASHM: Australasian contact tracing guidelines 2022 
• The Australian immunisation handbook 
• The Royal Australian College of General Practitioners: Guidelines for preventive activities in general practice 
• ASHM guidelines regarding eligibility for PrE
• ASHM and Queensland Health: Chlamydia and gonorrhoea testing
• ASHM: Hepatitis B virus testing and interpreting test results

Tools

• ASHM: Interactive syphilis decision-making tool 
• ASHM: Decision making in syphilis 
• ASHM: PrEP decision-making tool 
• ASHM: REACH-C – prescribing medications for hepatitis C. The online REACH-C form provides a time-effective option to receive specialist approval within 24 hours 
• ASHM: Decision making in hepatitis B 
• ASHM: Decision making in hepatitis C

Contact tracing resources

• Contact tracing for Aboriginal and Torres Strait Islander people 
• MSM 

Patient resources

• Better to Know – a sexual health resource for Aboriginal and Torres Strait Islander people 
• PrEP factsheet 
• Take Blaktion 
• Yarnin’ About Hep C resource 
• Us Mob and HIV – useful information on HIV and specifically for Aboriginal and Torres Strait Islander people 
• Young Deadly Free – a one-stop shop for resources about STIs and BBVs affecting young people in regional and remote Aboriginal and Torres Strait Islander communities 

Other resources for health professionals

• Patient-delivered partner therapy 
• ASHM training, including information on s100 prescribing for hepatitis B virus and HIV 

Reporting abuse

• Australian Institute of Family Studies information 
• Contact details by State and Territory jurisdiction 

Background

STIs and BBVs are responsible for considerable health, economic and social burdens globally.¹⁹ Higher rates of STIs and BBVs persist in Aboriginal and Torres Strait Islander populations, particularly in many remote and regional communities in Australia. Aboriginal and Torres Strait Islander adolescents and young people in particular are disproportionately affected by STIs²⁰ and BBVs.²¹ Most chlamydia and gonorrhoea notifications for both non-Indigenous and Aboriginal and Torres Strait Islander populations are for those in the 15- to 29-year age bracket.⁵ 

STIs and BBVs are often asymptomatic and may cause long-term sequelae, particularly for women.² STIs are associated with infertility and both maternal and infant complications in pregnancy. For this reason, antenatal STI and BBV screening and care are imperative, especially for Aboriginal and Torres Strait Islander women, who tend to commence families at a younger age (and are therefore in the age range associated with a higher prevalence of STIs) and have higher fertility rates than non-Indigenous Australian women.² STIs are associated with an increased risk of acquiring and transmitting BBV, particularly HIV.

BBVs are carried in the blood and can be spread through exposure to contaminated blood products, high-risk injecting activities, sexual contact, vertically from mother to child and through unsterile tattooing or body piercing. BBV notification rates are higher among Aboriginal and Torres Strait Islander peoples than among non-Indigenous Australians.^22,23 Higher rates of STIs and intravenous drug use (in particular receptive equipment sharing) and poorer access to some prevention measures, including HIV PrEP, pose important risks for preventing transmission and achieving the virtual elimination of HIV.

Many factors contribute to these higher rates of STIs and BBVs. Social determinants of health are defined as the non-medical factors that influence health outcomes and include:

• income; education, health literacy and knowledge regarding health system navigation and STIs²⁴
• employment; food security; housing; social inclusion; social networks/support; and access to culturally appropriate health services.²⁵

Poverty, discrimination, incarceration, mental ill-health and harmful substance use also affect sexual behaviours and can be associated with an increased risk of STIs and BBVs.²⁶ STIs and BBVs are frequently associated with shame and social stigma, and can be associated with interpersonal violence.^4,27 High rates of STIs in remote Australia are the result of a complex interplay of factors, which include:

• existing high rates in some communities mean that young people are more likely to be exposed at their first and each sexual encounter
• health services may not be accessible for various reasons (including lack of cultural safety, proximity and perceived lack of confidentiality)
• pathogen factors (eg asymptomatic chlamydia infection) may contribute to transmission prior to diagnosis and treatment.³

Regular testing is key to reducing rates of STIs and BBVs and, for many infections, there are effective preventive measures and treatments. This topic outlines the key strategies for preventing and detecting STIs and BBVs in Aboriginal and Torres Strait Islander populations. Management of specific STIs and BBVs is available in clinical and local guidelines (see Useful resources).

Specific STIs and BBVs

Chlamydia

Chlamydia trachomatis is the most diagnosed STI. Chlamydia is frequently asymptomatic, particularly in women, but infection may ascend to the upper reproductive organs, causing pelvic inflammatory disease and scarring (adhesions), chronic pelvic pain, ectopic pregnancy and infertility.²⁸ Chlamydial infection in men may cause urethral discharge (urethritis), testicular pain (epididymitis) and reactive arthritis.⁵

Chlamydia can be transmitted from mother to baby during birth, causing conjunctivitis, pneumonia and otitis media.⁵ Chlamydia infection in adults is easily tested for with a first-pass urine sample (first part of the urine stream passed) or low vaginal or anal swab (which may be self-collected by the patient) and, if uncomplicated, can be treated simply⁵ (see chlamydia and gonorrhoea testing in Useful resources)).

Gonorrhoea

Gonorrhoea is more common in MSM and young Aboriginal and Torres Strait Islander people living in rural and remote areas; however, its incidence is increasing in young women.⁵ Gonorrhoea is caused by Neisseria gonorrhoeae. It is often asymptomatic, but can cause pelvic inflammatory disease in women, which, like chlamydia, can lead to chronic pelvic pain, ectopic pregnancy and infertility. Throat and rectal gonorrhoea are generally asymptomatic, but most men with urethritis, proctitis, epididymitis and, occasionally, prostatitis experience symptoms. Infection acquired during oral sex can lead to pharyngitis, and disseminated infection from genital and/or oral sex can cause gonococcal septic arthritis.⁵ Infection during pregnancy can cause premature rupture of the membranes, and infection at birth can result in neonatal gonococcal conjunctivitis.²⁹

Gonorrhoea is tested for with first-pass urine, endocervical or low vaginal swabs and/or anal swabs, as appropriate. Low vaginal and anal swabs can be self-collected. Pharyngeal swabs may be taken where there is suspicion of gonococcal pharyngitis. Patterns of gonococcal antibiotic resistance vary, so consulting local guidelines is particularly important for treatment options.

Trichomoniasis

Trichomonas vaginalis is a sexually transmissible protozoal infection with highly variable prevalence reported.⁵ In Australia, trichomoniasis is more common in Aboriginal and Torres Strait Islander populations and in remote compared with urban populations.^5,30 Penile infection may resolve more quickly than vaginal infection, which may become chronic if left untreated. Trichomoniasis infection increases the risk of serious complications in pregnancy, such as preterm delivery and low birth weight,^30,31 and may increase the transmission of HIV.³² Testing is by low vaginal swab (which may be self-collected) or first-pass urine. Managing trichomoniasis infection in pregnancy requires specialist advice. Testing for trichomoniasis in patients presenting with urethritis is not routinely recommended and screening is only recommended in populations with high prevalence. Contacts should be treated presumptively (ie without necessarily testing).⁵ 

Syphilis

Syphilis is a highly infectious STI caused by Treponema pallidum bacteria. A lesion, a painless genital ulcer called a ‘chancre’, is usually, but not always, present for sexual transmission to occur.⁵ Syphilis is predominantly spread during unprotected vaginal, anal or oral sex or through skin-to-skin contact. Importantly, syphilis can be transmitted during pregnancy from mother to baby.^5,7 Complications of newly acquired syphilis include pregnancy loss and congenital syphilis, which is a significant cause of infant morbidity and mortality.⁷ Longer-term sequelae are rare but include neurosyphilis and cardiac complications.⁵

Syphilis is highly contagious in the first two years after infection, particularly during the primary and secondary stages, but also in the early part of the latent stage.⁵ Vertical transmission to an unborn baby can occur for even longer (ie into the late latent) period.⁵

Following newly acquired syphilis, there is often a latent phase when secondary syphilis may develop. Latent syphilis is an asymptomatic infection and is diagnosed by positive syphilis serology where there have either been no previous tests or more than two years since the last negative test. Latent syphilis is usually only transmitted vertically from mother to child, not to sexual partners; however, if secondary syphilis develops with symptoms, the patient is once again infective to partners until the symptoms resolve.⁵

Syphilis in pregnancy (congenital syphilis) is a cause of stillbirth, miscarriage, prematurity, neonatal death, low birth weight and organ damage in infants.⁷ In early infancy, congenital syphilis may be asymptomatic,³³ but symptoms and death may occur later.⁷ Early clinical features may include anaemia, failure to thrive, mucocutaneous lesions, hepatosplenomegaly, jaundice and lymphadenopathy. Later features include eye lesions, deafness, dental deformities, bone and joint lesions and central nervous system involvement. All babies born to a mother with reactive syphilis serology should be assessed by a paediatrician with specialist skills in infectious diseases.³⁴

Australia is in the midst of a national syphilis outbreak. Between July 2023 and June 2024 there were 5,963 notifications of infectious syphilis . The infectious syphilis notification rate in Aboriginal and Torres Strait Islander people is seven-fold higher than that of non-Indigenous Australians. Between 2016 and Q2 2024, there were 95 notifications of congenital syphilis and over half (52) of these were in Aboriginal and Torres Strait Islander infants.²⁴ nfectious syphilis diagnosed during pregnancy requires urgent treatment and specialist care.⁵

Syphilis notifications are also high in MSM.^5,36 Syphilis diagnosis can be complicated and, where there is doubt, specialist opinion should be sought. Diagnosis is made by a combination of serology, polymerase chain reaction (PCR) analysis of any lesions (eg chancre), history and clinical assessment.⁵ Highly specific treponemal antibody syphilis tests usually remain positive for years and are a poor marker of disease activity.⁵ Screening, including through point-of-care testing (POCT) where available, is an important control measure. When syphilis is diagnosed, prompt treatment, notification to the local public health unit to manage contact tracing and follow-up are key, as per clinical guidelines.⁵ In the event of a diagnosis of syphilis where there is any uncertainty of results, early discussion with a sexual health specialist is highly recommended.⁵

Human papillomavirus

Approximately 90% of the general population will be infected with at least one genital strain of HPV during their lifetime.³⁷ HPV genotypes 16 and 18 are the causative agents in 70–80% of all cervical cancers and are implicated in oropharyngeal, vulval, vaginal, anal and penile cancers.³⁸ HPV genotypes 6 and 11 are associated with 90% of genital warts⁵ and are rarely associated with cancer.³⁹ HPV vaccination is publicly funded for people aged 25 years and under and included in the National Immunisation Program (refer to Chapter 3: Immunisation across the life course and Chapter 19: Cancer prevention and early detection, Cervical cancer).

Hepatitis B

Hepatitis B is a common BBV and cause of cirrhosis and subsequent hepatocellular carcinoma (liver cancer) in Australia. The lifetime risk of cirrhosis is 20–30% in those who contract hepatitis B perinatally or in early childhood.⁸ Timely treatment reduces the progression to cirrhosis and induces some regression of cirrhosis in 70% of cases,⁴⁰ thereby decreasing the risk of developing hepatocellular carcinoma (see Chapter 19: Cancer prevention and early detection, Liver cancer).

Hepatitis B is spread through contaminated bodily fluids such as blood, semen and vaginal fluid (but, importantly, not saliva). Over two-thirds (72%) of people living with chronic hepatitis B in Australia are from culturally and linguistically diverse populations and Aboriginal and Torres Strait Islander people, most of whom have had hepatitis B since birth (due to vertical transmission) or early childhood.⁵ Hepatitis B infection is preventable through vaccination. Vaccine coverage of Aboriginal and Torres Strait Islander children in 2021 was 97% at 24 months of age and equivalent to that of non-Indigenous Australian children.^41,42 However, coverage at 12 months of age was 92% for Aboriginal and Torres Strait Islander children, compared with 95% of non-Indigenous Australian children.⁴²

Hepatitis B is more likely to be chronic if acquired in the perinatal or early childhood periods. Therefore, screening during pregnancy, administering hepatitis B immunoglobulin to neonates born to HBsAg-positive mothers and childhood vaccination commencing at birth for all babies are essential steps in preventing hepatitis B transmission.

Hepatitis C

Hepatitis C is a BBV that can become a chronic condition in approximately 75% of people who become infected, but is curable with direct-acting antiviral (DAA) treatment and can be treated multiple times. Chronic hepatitis C infection over many years can cause cirrhosis, liver failure and liver cancer (hepatocellular carcinoma).⁴³ In Australia, over 115,000 people are currently living with chronic hepatitis C, with many unaware they have it.⁴⁴ Aboriginal and Torres Strait Islander people are disproportionately affected by hepatitis C infection, making up 11% of all notifications, and incarceration represents a significant risk factor for transmission.⁴⁵ For people who inject drugs, it is important to ensure there is access to NSPs or other means of accessing clean injecting material in the community and in justice settings to reduce transmission.⁵

Hepatitis C is diagnosed via a blood test for hepatitis C antibody and HCV RNA. Point-of-care testing is increasingly available and can expedite diagnosis and treatment. Treatment with DAAs, which target multiple points in the hepatitis C replication lifecycle, is safe and effective, and the treatment duration is short.⁴⁵ Treatment should be offered whether or not the person continues to be exposed to risk of recurrent infection. DAAs can be prescribed by GPs. See Useful resources) for treatment guidelines and training resources.

HIV

HIV notifications have declined in Australia since 2016. HIV prevalence is highest among gay, bisexual and MSM groups, and transmission is now minimal among sex workers and people who inject drugs.⁴⁶ However, there are relatively higher HIV rates among Aboriginal and Torres Strait Islander people who inject drugs.²² In 2022, an estimated 29,460 people were living with HIV in Australia, 95% of whom had an undetectable viral load.⁴⁷ In 2020, the HIV notification rate in Aboriginal and Torres Strait Islander people was 2.2 per 100,000 population, a decrease from 3.6 to 6.3 per 100,000 population between 2011 and 2016 and equivalent to rates in non-Indigenous Australian-born people (2.3 per 100,000 population).⁴⁷

Earlier diagnosis and treatment of HIV increases the chances of the individual living a full and healthy life and reduces transmission. Untreated HIV can progress to AIDS over an average period of 10 years.

Although HIV can be tested for using a fingerprick dried blood spot test (POCT), this is not widely available in Australia and the usual test is on a blood sample sent to a laboratory for blood serology (HIV antibody/antigen). Consult local guidelines or the ASHM website for further information on testing for HIV (see Useful resources)).

Those with HIV should be treated with antiretroviral therapy. The aim of treatment is to achieve undetectable viral loads, which prevents transmission of HIV (ie undetectable = untransmissible) and disease progression.⁵ Prescribing antiviral therapy by GPs requires completion of HIV s100 prescriber training (see Useful resources)). Consult clinical guidelines and sexual health/infectious disease specialists for advice on treatment options and prevention using PrEP.

Immunisation

Human papilloma virus

HPV vaccination is recommended for:

• adolescents aged 9–25 years
• MSM
• people who are significantly immunocompromised, except for those with hyposplenia or asplenia.

The recommended schedule for adolescents starting the vaccine regime aged 9–25 years is one single dose. Those starting the vaccination regime aged 26 years and older should receive three vaccine doses, separated by a two-month interval between Doses 1 and 2 and a 4four-month interval between Doses 2 and 3. For immunocompromised individuals, regardless of age, the recommendation is three doses, separated by a two-month interval between Doses 1 and 2 and a four-month interval between Doses 2 and 3.³⁷

Hepatitis B

Universal childhood hepatitis B vaccination is included in the National Immunisation Program Schedule.⁴⁸ Although hepatitis B vaccination is now funded for non-immune Aboriginal and Torres Strait Islander adults in most states and territories, uptake is low, which may be due to low testing rates, and therefore not identifying non-immune adults. In states and territories without free access, the cost of the vaccine is a significant barrier to effective prevention. See Box 2 for groups to target for hepatitis B vaccination.

Screening

A sexual history should ideally be taken, but it is not imperative, and STI/BBV testing should be offered opportunistically at least annually and routinely included in general health assessments for everyone who is sexually active under the age of 30 years, and up to age 34 years in remote areas. A standard asymptomatic STI check should include chlamydia, gonorrhoea, trichomonas (in high-prevalence areas), syphilis, HIV and hepatitis B (unless immune status is known).^9,10

Annual screening in Aboriginal and Torres Strait Islander communities has been shown to decrease local STI prevalence, particularly if the screening program has good coverage of younger people.⁴⁹

It is important to normalise the discussion about testing for STIs using phrases such as ‘We routinely test for several things including STIs as part of a health assessment’ or ‘We are offering STI testing to all sexually active people under the age of 30/34 because STIs are very common and it is important to treat them early’.⁵ Many young Aboriginal and Torres Strait Islander people feel more comfortable discussing sexual health when there is an Aboriginal and/or Torres Strait Islander health worker or care provider present.⁵⁰ Guidelines for a thorough sexual history may be accessed via the ASHM website (see Useful resources).

Standard asymptomatic STI checks are recommended for people who:

• are aged 15–29 years, and up to 34 years if living in remote areas, who are/have been sexually active
• request STI testing
• have an increased risk of STIs:
  • new sexual partner(s)
  • living in or travelling to areas of high STI prevalence
• have a known exposure or history of STI within the previous year
• are a sexual partner of any of the above.

Nucleic acid amplification tests or PCR tests from urine or swabs have a high sensitivity and specificity for chlamydia, gonorrhoea and trichomonas.⁵ POCT is increasingly used in community and custodial settings, with comparable sensitivity and specificity to PCR, and a rapid result within 90 minutes.⁵¹ By avoiding delay between testing and results, POCT may circumvent known issues such as loss to follow-up, challenging outreach and incomplete treatment. However, POCT requires additional funding, may increase workload for clinicians and may require training and quality management.⁵²

One-time screening for hepatitis B, which has been shown to be cost-effective down to a low population prevalence, and targeted screening of people at high risk of hepatitis C are essential to identify people at increased risk of cirrhosis and liver cancer in order to offer monitoring and antiviral treatment as well as vaccination for hepatitis B non-immune adults.^53–55 All Aboriginal and Torres Strait Islander people should have hepatitis B immune or infectious status known and documented in their health record.

Testing should include:

• anti-HBs antibody, indicating immunity (vaccination or infection)
• HBsAg, indicating active infection (acute or chronic)
• anti-HBc antibody, indicating infection (past or current).

All those who are HBsAg negative should be offered a course of hepatitis B immunisation and all those with infection should be referred for treatment and actively monitored with regular review.⁵⁶

For women who are pregnant, at the first antenatal visit offer testing for hepatitis B, hepatitis C, HIV, syphilis, chlamydia (for pregnant people aged under 30 years or 34 years if in a remote area) and gonorrhoea (for pregnant people aged under 30 years or 34 years if in a remote area). Syphilis testing should be repeated in the third trimester of pregnancy, and more frequently if in high-prevalence areas or when there are additional risk factors. If the pregnant woman is at high risk of syphilis (eg partner of an MSM; living in remote Aboriginal and Torres Strait Islander communities) a further test at six weeks postpartum is recommended. If the pregnant woman has symptoms of syphilis, seek urgent specialist advice.⁵ These guidelines vary between jurisdictions, and it is advisable to check local guidelines.

Cervical HPV screening is available for women aged 25–74 years and should be offered as part of sexual health checks, including in pregnancy, as per current guidelines¹² (see Chapter 19: Cancer prevention and early detection, Cervical cancer).

Contact tracing

Contact tracing is the process of notifying sexual contacts of a person with an STI or BBV. Contact tracing is a key part of effective prevention and management of STIs and BBVs. The GP or nominated clinician within the health service, such as a sexual health nurse, may undertake contact tracing, and/or seek assistance from local sexual health physicians or contact tracers.

In many cases, contact tracing can be performed by the index case (patient) with the support of the diagnosing clinician. In some circumstances, where the source of infection is not immediately identifiable, specialist advice may be required.

There may be culturally specific factors that contribute to sensitivities and stigma for Aboriginal and Torres Strait Islander people in relation to sexual health, and it is important for all clinicians, especially non-Indigenous Australian clinicians, to establish trust to ensure effective engagement. Aboriginal and Torres Strait Islander health workers play a valuable role in bridging cultural gaps in healthcare. A holistic model of care should be used to improve healthcare outcomes, with consideration to gender-sensitive practice, including men’s business and women’s business, as well as the gender of the clinician and contact tracer. Other important considerations are client mobility, which may lead to loss to follow-up, multiple client identifiers, multiple client addresses and multiple people using one mobile phone number. Clients need clarity regarding the prognosis following diagnosis, and it is recommended that clinicians confirm the client’s first language is English and, if not, to source culturally appropriate services for translation, with consideration to small community sizes and confidentiality.

With a sustained undetectable viral load, a person living with HIV cannot transmit the infection to an HIV-negative partner. However, those with newly diagnosed HIV, or a detectable viral load, can often transmit HIV unknowingly, and contact tracing is required. A discussion with the index case and patient-referred contact tracing is preferred; however, if this is unachievable, referral to specialist services is recommended.

People who inject or use drugs may be socially isolated and economically disadvantaged, and contact tracing may be challenging in this population. It is advisable to work closely with the index case to engage them in supported contact tracing.

Conditions where contact tracing is required and specifics are provided in Table 2.⁵⁷ For contact tracing in Aboriginal and Torres Strait Islander populations, see Useful resources>.

Behavioural changes

STI testing can include opportunistic education and sexual health counselling regarding safe sex practices, including condom (or other barrier) use and provision. Condom use significantly reduces the risk of STI transmission and is an effective method for preventing HIV transmission. If the sexual history indicates condoms are not used consistently, explore barriers and enablers to their use. Condoms are recommended in new relationships until both partners have had an STI check. Excessive alcohol consumption and illicit drug use are associated with increased sexual risk behaviours and STIs.^58,59

It is important to be familiar with state and territory legislation regarding sexual activity in individuals aged younger than 18 years and mandatory jurisdictional reporting requirements where abuse is suspected (see Useful resources, Reporting abuse).

Chemoprophylaxis

Chemoprophylaxis is available for people at risk of HIV. There are two types of chemoprophylaxis for HIV: PrEP and PEP. Importantly, for HIV transmission, an undetectable viral load means that HIV cannot be transmitted; thus, it is important that people living with HIV are effectively treated to prevent further transmission.

Pre-exposure prophylaxis

PrEP is the use of antiretrovirals by HIV negative people to prevent HIV acquisition. PrEP may be taken daily or around the time of a sexual encounter. ASHM guidelines (2019) recommend daily PrEP for all people at risk of HIV infection and that on-demand PrEP be offered as an alternative option to cisgender MSM.¹⁵ All GPs and other medical specialists can prescribe PrEP using a Pharmaceutical Benefits Scheme authority arrangement, and no specialist training is required to do this. ASHM provides resources and training guides for clinicians who are new to prescribing PrEP.¹⁵ New guidelines emphasise the importance of broadening access to PrEP for people who are at medium or high risk of acquiring HIV.⁶⁰ The ASHM website (see Useful resources) provides comprehensive resources on suitability for PrEP, and it is important to note that eligibility is reviewed at each three-monthly follow-up.

For cisgender and transgender men and gender diverse people who have sex with men, the clinician and patient should discuss PrEP if the patient requests it or if the healthcare professional believes there is a risk of having acquired HIV in the previous three months and it is likely there will be further risks in the following three months. These risks include (but are not limited to): condomless anal intercourse with an HIV-positive partner who has a detectable HIV load; anal intercourse with a casual male partner; episodes of sexualised drug use (‘chemsex’); rectal gonorrhoea or chlamydia; infectious syphilis; or anal intercourse with a condom that did not remain intact. Assessing future risk should consider the travel plans of the patient, residence in correctional facilities, mental health and drug/alcohol use.⁶⁰ For people who inject drugs, the clinician should consider prescribing PrEP for those sharing injecting equipment, engaging in sexual risk behaviours and entering or leaving institutional correctional facilities.⁶⁰ All patients interested in commencing PrEP must have a documented negative HIV test at the time of testing because the dosage used in PrEP is insufficient for treatment of disease. HIV testing must be completed every three months at the time of prescription refill. Rapid POCT should not be used for this pre-PrEP screening. At baseline, there should also be a complete STI and BBV screen and assessment of renal function, bone health and pregnancy.⁶⁰

Post-exposure prophylaxis

PEP is recommended for exposures where the source is HIV positive with an unknown or detectable viral load or where the source is from a high-prevalence population (including MSM or high-prevalence country). PEP should be commenced within 72 hours of exposure to be effective.¹⁶ Decisions on commencing PEP and PEP treatment courses are based on the mode of transmission and the HIV status of the source and exposed individuals. If the individual requiring PEP is pregnant or lactating, aged under 16 years or has hepatitis B or C, seek specialist input.¹⁶ PEP is not required for oral intercourse.¹⁶ PEP can be accessed at any hospital emergency department or through s100 prescribers (GPs and authorised nurse practitioners) who are trained in HIV prescribing.
 

Environmental changes

Condom availability

Access to free condoms is important considering how effective they are in preventing HIV and STI transmission. Free condoms at public venues have been shown to effectively reduce the transmission of HIV and other STIs in MSM.¹⁷ Many Aboriginal and Torres Strait Islander Community Controlled Health Organisations (ACCHOs) provide free condoms in their health services or close by. The Ending HIV program website provides a map for accessing free condoms and water-based lubricant.⁶¹ In Queensland, the Stop the Rise of STIs initiative run by the Queensland AIDS Council provide free safe sex packs containing condoms, female condoms and lubricant to people at risk of STIs and HIV, and health services and other jurisdictions have similar initiatives.⁶²

Needle and syringe programs

Community-based NSPs are key harm-reduction strategies to prevent the transmission and incidence of BBVs in injecting drug users,^63,64 and there is little evidence for negative unintended consequences.⁶⁴ NSPs involve the provision of clean and sterile injecting materials and sharps bins for the safe disposal of injecting equipment.¹⁸ In community settings, NSPs have been shown to decrease needle sharing rates from 70–90% to 17% and to reduce BBV prevalence in injecting drug users to <1%.⁶³ International literature indicates that NSPs are highly cost-effective compared with the costs of treating BBVs such as HIV.⁶⁵ From 2000 to 2009, NSPs in the Australian Capital Territory resulted in an estimated net cost saving of $2.6 million and of over 2000 disability-adjusted life years.⁶⁵ GPs and primary care teams should be aware of the location of NSPs in their area. Despite good outcomes and cost-effectiveness, NSPs are not available in custodial settings, where the prevalence of injecting drug use is higher and the risk of sharing equipment greater.¹⁸
 
BBVs such as HIV and hepatitis C disproportionately affect people in custodial settings, and Aboriginal and Torres Strait Islander people and injecting drug users are also over-represented in this population.^45,66 The transmission of BBVs such as HIV and HCV in custodial settings is often due to injecting drug use.⁶⁷ One study reported that the per-sharing event probability of HCV transmission in people who inject drugs was 0.57% (95% confidence interval 0.32–1.05%).⁶⁸ Injecting drug use overall is uncommon among Aboriginal and Torres Strait Islander populations,¹³ but studies have shown that when injecting drugs are used, needle sharing is more prevalent than within the non-Indigenous Australian population.⁶⁹ This culture of sharing is likely to be a factor contributing to the high prevalence of BBVs within custodial settings, in addition to the lack of access to NSPs and lack of testing of and treatment of BBVs.

STI testing can include opportunistic education and sexual health counselling regarding safe sex practices, including condom (or other barrier) use and provision. Condom use significantly reduces the risk of STI transmission and is an effective method for preventing HIV transmission. If the sexual history indicates condoms are not used consistently, explore barriers and enablers to their use. Condoms are recommended in new relationships until both partners have had an STI check. Excessive alcohol consumption and illicit drug use are associated with increased sexual risk behaviours and STIs.^58,59 

It is important to be familiar with state and territory legislation regarding sexual activity in individuals aged younger than 18 years and mandatory jurisdictional reporting requirements where abuse is suspected (see Useful resources, Reporting abuse).
 

Chemoprophylaxis

Chemoprophylaxis is available for people at risk of HIV. There are two types of chemoprophylaxis for HIV: PrEP and PEP. Importantly, for HIV transmission, an undetectable viral load means that HIV cannot be transmitted; thus, it is important that people living with HIV are effectively treated to prevent further transmission. 

Pre-exposure prophylaxis

PrEP is the use of antiretrovirals by HIV negative people to prevent HIV acquisition. PrEP may be taken daily or around the time of a sexual encounter. ASHM guidelines (2019) recommend daily PrEP for all people at risk of HIV infection and that on-demand PrEP be offered as an alternative option to cisgender MSM.¹⁵ All general practitioners and other medical specialists can prescribe PrEP using a Pharmaceutical Benefits Scheme authority arrangement, and no specialist training is required to do this. ASHM provides resources and training guides for clinicians who are new to prescribing PrEP.¹⁵ New guidelines emphasise the importance of broadening access to PrEP for people who are at medium or high risk of acquiring HIV.⁶⁰ The ASHM website (see Useful resources) provides comprehensive resources on suitability for PrEP, and it is important to note that eligibility is reviewed at each three-monthly follow-up. 

For cis- and transgender men and gender diverse people who have sex with men, the clinician and patient should discuss PrEP if the patient requests it or if the healthcare professional believes there is a risk of having acquired HIV in the previous three months and it is likely there will be further risks in the following three months. These risks include (but are not limited to): condomless anal intercourse with an HIV-positive partner who has a detectable HIV load; anal intercourse with a casual male partner; episodes of sexualised drug use (‘chemsex’); rectal gonorrhoea or chlamydia; infectious syphilis; or anal intercourse with a condom that did not remain intact. Assessing future risk should consider the travel plans of the patient, residence in correctional facilities, mental health and drug/alcohol use.⁶⁰ For people who inject drugs, the clinician should consider prescribing PrEP for those sharing injecting equipment, engaging in sexual risk behaviours and entering or leaving institutional correctional facilities.⁶⁰ All patients interested in commencing PrEP must have a documented negative HIV test at the time of testing because the dosage used in PrEP is insufficient for treatment of disease. HIV testing must be completed every three months at the time of prescription refill. Rapid POCT should not be used for this pre-PrEP screening. At baseline, there should also be a complete STI and BBV screen and assessment of renal function, bone health and pregnancy.⁶⁰ 

Postexposure prophylaxis

PEP is recommended for exposures where the source is HIV positive with an unknown or detectable viral load or where the source is from a high-prevalence population (including MSM or high-prevalence country). PEP should be commenced within 72 hours of exposure to be effective.¹⁶ Decisions on commencing PEP and PEP treatment courses are based on the mode of transmission and the HIV status of the source and exposed individuals. If the individual requiring PEP is pregnant or lactating, aged under 16 years or has hepatitis B or C, seek specialist input.¹⁶ PEP is not required for oral intercourse.¹⁶ PEP can be accessed at any hospital emergency department or through s100 prescribers (general practitioners and authorised nurse practitioners) who are trained in HIV prescribing. 

Condom availability

Access to free condoms is important considering how effective they are in preventing HIV and STI transmission. Free condoms at public venues have been shown to effectively reduce the transmission of HIV and other STIs in MSM.¹⁷ Many Aboriginal and Torres Strait Islander Community Controlled Health Organisations (ACCHOs)provide free condoms in their health services or close by. The Ending HIV program website provides a map for accessing free condoms and water-based lubricant.⁶¹ In Queensland, the Stop the Rise of STIs initiative run by the Queensland AIDS Council provide free safe sex packs containing condoms, female condoms and lubricant to people at risk of STIs and HIV, and health services and other jurisdictions have similar initiatives.⁶² 

Needle and syringe programs

Community-based NSPs are key harm reduction strategies to prevent the transmission and incidence of BBVs in injecting drug users,^63,64 and there is little evidence for negative unintended consequences.⁶⁴ NSPs involve the provision of clean and sterile injecting materials and sharps bins for the safe disposal of injecting equipment.¹⁸ In community settings, NSPs have been shown to decrease needle sharing rates from 70–90% to 17% and to reduce BBV prevalence in injecting drug users to <1%.⁶³ International literature indicates that NSPs are highly cost-effective compared with the costs of treating BBVs such as HIV.⁶⁵ From 2000 to 2009, NSPs in the Australian Capital Territory resulted in an estimated net cost saving of $2.6 million and of over 2000 disability-adjusted life years.⁶⁵ General practitioners and primary care teams should be aware of the location of NSPs in their area. Despite good outcomes and cost-effectiveness, NSPs are not available in custodial settings, where the prevalence of injecting drug use is higher and the risk of sharing equipment greater.¹⁸ 

BBVs such as HIV and hepatitis C disproportionately affect people in custodial settings, and Aboriginal and Torres Strait Islander people and injecting drug users are also over-represented in this population.^45,66 The transmission of BBVs such as HIV and HCV in custodial settings is often due to injecting drug use.⁶⁷ One study reported that the per-sharing event probability of HCV transmission in people who inject drugs was 0.57% (95% confidence interval 0.32–1.05%).⁶⁸ Injecting drug use overall is uncommon among Aboriginal and Torres Strait Islander populations,¹³ but studies have shown that when injecting drugs are used, needle sharing is more prevalent than within the non-Indigenous population.⁶⁹ This culture of sharing is likely to be a factor contributing to the high prevalence of BBVs within custodial settings, in addition to the lack of access to NSPs and lack of testing of and treatment of BBVs.