What are STIs?

STIs (sexually transmissible infections) are infections that are passed on through close body contact or the exchange of body fluids.

Many people who have an STI don’t have any obvious symptoms or signs, so it’s important you get the facts about how they are spread, how to avoid infection, understand the risks if left untreated, and know what to do if you think you may have one.

How are STIs caused?

Like other infections or diseases, STIs are caused by the spread of organisms like bacteria, viruses or parasites. STIs caused by bacteria include chlamydia, gonorrhoea and syphilis. STIs caused by viruses include herpes, HIV (human immunodeficiency virus), HPV (human papillomavirus) and hepatitis B.

How common are STIs?

Unfortunately, STIs are more common than you might think. In 2009, the total number of reported STIs in Australia was over 70,000 – including HIV, the virus that can cause AIDS. The true number may be much higher, as many people who have had unprotected sex haven’t been tested for STIs.

Three quarters of reported STIs occur in people aged between 15 and 29 years.

Do STIs lead to long term damage?

If left untreated STIs can lead to serious and painful health consequences, ranging from infertility to cancer. For example, chlamydia and gonorrhoea can cause inflammation and scarring of the fallopian tubes in women which could lead to infertility. In men, the same complications might occur in the tubes leading from the testicles which could also cause fertility problems, though it’s much less common. Syphilis can cause blindness, brain damage and heart disease.

These three infections are easy to test for and to cure. It is really important that people with STIs are diagnosed early so they can receive proper treatment and avoid ongoing health problems and spreading the infection.

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Do STIs have symptoms?

Many people with an STI have no symptoms whatsoever, and they can only be diagnosed through testing. If signs and symptoms are present they may include things like:

• unusual discharge from the penis, vagina or anus
• itchiness around the genital area
• a burning sensation when peeing
• a rash, sores or small lumps on or around the penis, vagina or anus
• unusual bleeding from the vagina e.g. after sex or between periods
• pain and swelling in the testicles
• pain during sex
• sore throat
• swollen glands, fever and body aches
• unexplained fatigue, night sweats and weight loss