Latest information and statistics on sexual health

Sexually transmissible infections

Sexually transmissible infections (STIs) include bacterial, viral and parasitic infections that are primarily transmitted through sexual contact [1]. Young people are particularly vulnerable to STIs. The use of condoms is regarded as fundamental in preventing STI transmission. Most STIs are treatable and early detection is important in the management of STIs.

Chlamydia

Chlamydia is an infection caused by the bacterium Chlamydia trachomatis and symptoms mainly consist of an inflamed urethra, causing discharge for males and pain during urination and intermenstrual bleeding for females [2]. However, chlamydia is asymptomatic (showing no symptoms) in about 80% of cases. Chlamydia can also lead to reproductive issues for females such as infertility, pelvic inflammatory disease and ectopic pregnancies.

In 2023 there were 8,557 notifications of chlamydia for Aboriginal and Torres Strait Islander people. The age-standardised notification rate1 for chlamydia among Aboriginal and Torres Strait Islander people was 820 per 100,000 [3]. The rate among females (1,028 per 100,000) was higher than for males (621 per 100,000). In 2023, The highest chlamydia notifications were among Aboriginal and Torres Strait Islander people aged 15-19 years (3,088: 36%), followed by 20-24 years (2,369: 28%) (Derived from [3]).

In 2023, for the jurisdictions reported, notification rates for chlamydia were highest in the NT (1,333 per 100,000), followed by WA (943 per 100,000) and Qld (517 per 100,000) [3]. The remaining jurisdictions reported on, had notification rates ranging from 284 per 100,000 in the ACT to 495 per 100,000 in SA. The notification rate for chlamydia increased with remoteness from 599 per 100,000 in major cities, 677 per 100,000 in regional areas to 2,374 per 100,000 in remote areas.

Gonorrhoea

Gonorrhoea is an infection caused by the bacterium Neisseria gonorrhoeae and displays similar symptoms to chlamydia [2]. Gonorrhoea is largely asymptomatic and can lead to reproductive issues if left untreated [2][4].

In 2023, there were 5,631 gonorrhoea notifications for Aboriginal and Torres Strait Islander people [3]. The age-standardised notification rate2 for Aboriginal and Torres Strait Islander people was 541 per 100,000. The notification rate for gonorrhoea among females (595per 100,000) was higher than for males (492 per 100,000).

In 2023, the highest gonorrhoea notifications were among Aboriginal and Torres Strait Islander people aged 15-19 years (1,529: 27%), followed by 20-24 years (1,335: 24% ) and 30-39 years (1,148: 20%) (Derived from [3]).

In 2023, notification rates for gonorrhoea were highest in the NT (2,200 per 100,000), followed by WA (877 per 100,000) and SA (875 per 100,000) [3]. The remaining jurisdictions reported on, had notification rates ranging from 99 per 100,000 in Tas to 360 per 100,000 in Qld. The notification rate for gonorrhoea increased by remoteness from 271 per 100,000 in major cities, 292 per 100,000 in regional areas to 1,819 per 100,000 in remote areas.

Syphilis

Syphilis is an infection caused by the bacterium Treponema pallidum which can be contracted through sexual contact, blood-to-blood contact and from mother to child during pregnancy [2][5]. If a fetus contracts syphilis during pregnancy it is called congenital syphilis, and often results in the fetus dying if left untreated. The primary symptom of syphilis is a painless ulcer located at the area of infection, which appears within the first couple of weeks after infection, followed by a rash, which usually appears on the palms of the hands or soles of the feet if left untreated and progresses into what is termed secondary syphilis. Following the secondary stage, the infection is asymptomatic.

In 2023, there were 1,022 syphilis notifications for Aboriginal and Torres Strait Islander people [3]. The age-standardised notification rate3 for Aboriginal and Torres Strait Islander people was 102 per 100,000. The notification rate for syphilis among females (104 per 100,000) was higher than for males (100 per 100,000).

In 2023, the highest syphilis notifications were among Aboriginal and Torres Strait Islander people aged 30-39 years (257: 25%), followed by 20-24 years and 15-19 years (205 and 203 respectively, both 20%) (Derived from [3]).

In 2023, notification rates for syphilis were highest in WA (242 per 100,000), followed by the NT (212 per 100,000) and Qld (103 per 100,000) [3]. The remaining jurisdictions had notification rates ranging from 18 per 100,000 in Tas, to 86 per 100,000 in SA.  The notification rate for syphilis was 70 per 100,000 in regional areas, 79 per 100,000 in major cities and 249 per 100,000 in remote areas.

Footnotes

1 Notification rates by Aboriginal and Torres Strait Islander status are only included for jurisdictions where Aboriginal and Torres Strait Islander status was reported for ≥50% of diagnoses for each of the reported years. For chlamydia this included NSW, Qld, WA, SA, the ACT and the NT.

2 Notification rates by Aboriginal and Torres Strait Islander status are only included for jurisdictions where Aboriginal and Torres Strait Islander status was reported for ≥50% of notifications for each of the reported years. For gonorrhoea this included all jurisdictions except Vic.

3 Notification rates by Aboriginal and Torres Strait Islander status are only included for jurisdictions where Aboriginal and Torres Strait Islander status was reported for ≥50% of diagnoses for each of the reported years. For infectious syphilis this included all jurisdictions.

Human immunodeficiency virus (HIV)

The human immunodeficiency virus (HIV) affects a person’s immune system and over time prevents their body’s ability to overcome infections and illnesses [6]. HIV can be transmitted through certain body fluids such as blood, vaginal fluid, semen and breast milk. It can also be transmitted during pregnancy or birth from mother to child. If untreated, HIV can progress to acquired immune deficiency syndrome (AIDS) [2].

The risk factors associated with contracting HIV include engaging in unprotected sex (anal, oral or vaginal), having an STI, sharing injecting equipment, using unsterile piercing and tattooing equipment or accidental needle stick injuries [6][7].

HIV symptoms often vary and develop over time, meaning it is common for people who are infected to be unaware they are HIV positive until the later stages of infection [6]. However, the most infectious time period is the first few months after infection.

In 2023, there were 24 notifications1 of HIV infection in Australia among Aboriginal and Torres Strait Islander people [3]. The median age of diagnosis was 40.5 years. The age-standardised rate of HIV notification for Aboriginal and Torres Strait Islander people was 2.9 per 100,000 population.

In 2023, the age-standardised HIV notification rate for Aboriginal and Torres Strait Islander males (3.8 per 100,000) was higher than for females (2.1 per 100,000) [3].

In 2023, the age-standardised HIV notification rate was higher among Aboriginal and Torres Strait Islander people aged 35 years and over (3.6 per 100,000) compared with those aged under 35 years (2.0 per 100,000) [3].

In 2023, NSW accounted for the most HIV notifications (11 cases: 49%) followed by Qld (8 cases: 33%) (Derived from [3]). The HIV notification rate was highest among Aboriginal and Torres Strait Islander people living in major cities (4.4 per 100,000), followed by remote areas (2.5 per 100,000) and regional areas (1.6 per 100,000) [3].

1 HIV notifications are based on small numbers so should be interpreted with caution.