What you need to know about STIs

Troubling new stats show some sexually transmitted infections are on the rise across Australia.

Chlamydia the most commonly reported sexually transmitted infection in Australia and it’s highly infectious.

But you may not even realise you’re infected, because it’s an STI that often shows no symptoms.

The number of people being diagnosed with chlamydia is increasing – and new national statistics from the Kirby Institute’s annual surveillance report show other STIs are also rising, including gonorrhoea and syphilis.

Kathleen McNamee of Family Planning Victoria says the statistics are a reminder that anyone who is sexually active and under the age of 30 should get screened every year.

“These STIs are treatable but they can lead to complications if they’re not diagnosed and treated,” she says.

Common STIs – and how to treat them


In 2017, there were 100,775 notifications of chlamydia. Just over half were in women and it was most prevalent in people aged 15 to 29.

“Chlamydia is most often picked up with a screening test – a urine test or a vaginal swab for women,” explains Kathleen.

“Women may get irregular bleeding, especially after sex, and people can get discharge or a stinging sensation when passing urine. Chlamydia can also cause pelvic pain.”

Treatment for chlamydia

A single dose of antibiotics. Sexual partners should also be tested and treated. Condoms reduce the risk of infection.


Cases of gonorrhoea rose 16 per cent, with 23,875 cases reported in 2017.

About three-quarters of cases were in men, with just over half in 15 to 29-year-olds.

It is most often spread by having sex without condoms and can infect the urethra, the cervix, anus and throat.

“Men get a pus-like discharge and pain passing urine. It’s often without symptoms for women but it can cause discharge, irregular bleeding or bleeding after sex and pelvic pain,” says Kathleen.

Treatment for gonorrhoea:

Antibiotics. Sexual partners also need to be tested.


Syphilis is one of the fastest rising STIs in Australia, with people aged 25 to 29 having the highest rate of infection and more men than women being diagnosed.

In the past 10 years, reports of syphilis have risen by 233 per cent.

Syphilis is a bacterial infection transmitted through unprotected sex and through skin-to-skin contact with an infected area. Condoms reduce the risk.

“The first stage is an ulcer or sore – sometimes unnoticed – around the anus, genitals or your mouth. That sore goes away but the syphilis doesn’t go away,” says Kathleen.

Other symptoms of syphilis include skin rashes, fever, swelling of glands in the groin and armpits, a genital rash and feeling tired.

Treatment for syphilis

Penicillin or other medication, if you have a penicillin allergy.

Written by Sarah Marinos.