Chlamydia

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What is chlamydia?

Chlamydia is a common sexually transmissible infection (STI) caused by the bacteria Chlamydia trachomatis. In women it generally affects the urethra and the cervix and sometimes the uterus, throat or anus. Because most people with chlamydia do not experience any symptoms it often goes undiagnosed. It is a major cause of infertility in women if left untreated.

Who gets it?

Both women and men are affected by chlamydia and anybody who has engaged in unprotected oral, vaginal or anal sexual activity is at risk. Queensland has the highest rate of diagnosis in Australia, with almost 20,000 people diagnosed in 2010. The rate of diagnosis in Queensland has increased 90 per cent since 2004 (1).

Although most people diagnosed are aged 16 to 24 (2) it is thought that longer life expectancy and an increased likelihood of having new sexual partners later in life are contributing to rising infection rates amongst older Australians (3). Having new sexual partners and not practicing safe sex increases a person’s risk.

Symptoms

Most people with chlamydia will not have any symptoms. This means that it can go undiagnosed for a long time, potentially leading to serious complications. If symptoms are present they may be overlooked as they can be similar to those of other conditions. For example, unusual bleeding may be misinterpreted as a side effect of hormonal contraception. If symptoms occur they generally appear 2 to 14 days after infection and can include:

In women

• pelvic pain
• painful and/or heavy periods
• deep pain during vaginal sex
• bleeding between periods or after having sex
• frequent and/or burning urination
• unusual vaginal discharge.

In men

• discharge from the penis
• burning or pain when urinating
• itching or irritation around the opening of the penis
• pain or soreness in the testicles.

Chlamydia infection and complications

In women chlamydia causes inflammation of the urethra (the tube from the bladder to the urinary opening) and/or the cervix (the neck of the uterus). If left untreated the infection can spread to the uterus, fallopian tubes and ovaries. When this occurs it is referred to as pelvic inflammatory disease (PID). PID is treated with antibiotics but it can be difficult to diagnose and may result in scar tissue forming in the pelvis. If scar tissue blocks the fallopian tubes it can cause infertility or place a woman at risk of ectopic pregnancy. PID is also associated with chronic pelvic pain. The risk of PID and tubal damage increases substantially with repeat chlamydia infections (4).

In men chlamydia causes inflammation of the urethra. If left untreated the infection can move to the epididymis (the tubes which carry sperm) and testes. This can cause severe pain, swelling and fever and usually requires hospital admission. This infection may cause scarring and, rarely, fertility problems.

Chlamydia and pregnancy

A pregnant woman infected with chlamydia has an increased risk of premature delivery (5). There is also a risk of the baby becoming infected with chlamydia during delivery, causing either conjunctivitis (eye infection) or pneumonia (chest infection).

Getting checked

Because chlamydia often does not have any symptoms it is important for women to have regular sexual check-ups, particularly after engaging in unsafe sexual activity, sexual activity with a new partner or with a partner who may have other partners. It is recommended that all sexually active women aged between 15 and 29 are tested at least annually (6).

Testing for chlamydia usually involves a simple urine test. Sometimes a swab of the cervix, anus or throat might also be taken. Chlamydia cannot be diagnosed with a Pap smear, although having a Pap test is a good opportunity for taking a swab from the cervix to test for chlamydia at the same time. Before testing, the health practitioner may ask a number of questions about a person's sexual history (e.g. number of partners, recent change of partners, use of condoms/dams) to determine that person's risk level. It can be a good idea to be tested for other STIs such as gonorrhoea, hepatitis B and HIV at the same time as being tested for chlamydia.

Queensland residents can order a free home testing kit from Queensland Health, allowing a urine sample to be posted directly for testing. Results are provided straight to the person who has been tested. For details on how to order a kit see Further information below. A number of home testing kits can also be bought online or from pharmacies. While offering the convenience of home-based testing, these kits can be expensive and the woman must nominate a doctor to receive the results rather than receiving them directly.

Treatment

Chlamydia is usually treated with a single antibiotic dose. If complications have occurred from the infection (e.g. PID) a longer antibiotic treatment may be necessary. To avoid re-infection, current sexual partners will also need to be treated. People are usually asked to return to their health practitioner following treatment to ensure the infection has been cleared and to check that current partners have been treated.

Notifying partners

Because chlamydia often does not have symptoms it is also important to contact sexual partners from the previous six months (7). It is important that current sexual partners are treated before resuming sexual activity. Health professionals can provide support and assistance in contacting previous partners, including anonymously if required. The Let Them Know website www.letthemknow.org.au can also be used to assist in notifying partners personally or anonymously via letter, SMS, email or in person.

Emotional impact

Being diagnosed with chlamydia can be distressing for some people. Questions concerning the source of infection may impact on a relationship. If there has been an assumption of mutual monogamy discussion about other sexual partners can be difficult.

It may help to remember that chlamydia is a very common infection that is easy to treat with antibiotics. If people are worried about having chlamydia they can talk to their health practitioner, a close friend or relative, or seek counselling. Women in Queensland can call the Health Information Line on 3839 9988 or 1800 017 676 (toll free from outside Brisbane) if they are concerned.

Prevention

The best protection from chlamydia and other STIs, whatever your sexual preference, is to always practise safe sex. Barrier protection (condoms, dams) should always be negotiated when having sex with a new or casual partner. Withdrawal (when the penis is withdrawn from the vagina before ejaculation) is not protective against chlamydia or any other STI. Because the risk of PID and tubal damage increases with repeat chlamydia infections, if a woman has had chlamydia in the past it is extremely important to avoid repeat infections.

Further information

Queensland Health Sexual Health website (including information on how to order a home testing kit)

Let Them Know – for help notifying sexual partners about chlamydia personally or anonymously

References

(1) Queensland Health 2011: Chlamydia accessed 26 October 2011.

(2) ibid.

(3) Pogson, Jenny 2011: Chlamydia at 50… Could it be you? accessed 26 October 2011.

(4) Guy R, Ali H, Liu B, Hocking J, Donovan B, Kaldor J 2011, Genital chlamydia infection in young people, a review of the evidence, report to the NSW Health Department by the Kirby Institute, University of New South Wales, p 4

(5) Victoria Department of Health 2007, Chlamydia (genital infection) accessed 27 April 2012.

(6) Queensland Health, Queensland Sexual Health Clinical Management Guidelines accessed 27 April 2012.

(7) ASHM 2010: Australasian Contact Tracing Manual accessed 10 November 2011.

For help understanding this fact sheet or further information on chlamydia or other STIs call the Health Information Line on 3839 9988 (within Brisbane) or 1800 017 676 (toll free outside Brisbane)

This factsheet was originally published by Women's Health Queensland Wide (Women's Health) in February 1999. It was revised by Kirsten Braun and the Editorial Committee in February 2002 and October 2006 and by Lorraine Pacey and the Editorial Committee in May 2012.

Last Modified: 14 May 2012