Chlamydia is the most common and treatable sexually transmitted bacterial infection. Chlamydia infects the cervix in girls and the urethra, rectum and eyes can be infected in both girls and boys. It can also live in other parts of the body such as the liver, lungs and throat.

In the UK rates of chlamydia infection are rising and it’s thought that around one per cent of females aged 16-19 have the infection. Chlamydia can cause serious problems later on in life if it’s not treated early on. The problem with this infection is that there are often no obvious symptoms and the infection is only diagnosed after you have complications. At this point treatment can sometimes be too late to stop permanent damage.

This is why it’s best to know all about chlamydia, how to prevent it and where you can get tested if you think you are at risk, so you can get early treatment – which is very effective.

What causes chlamydia and who can get it?

Chlamydia is caused by the chlamydia bacteria (Chlamydia trachomatis). It can be passed on through sexual intercourse or through oral sex. Chlamydia affects people who are sexually active, both male and female. It also strikes in all cultures and social groups, with young women being more at risk from the disease.

What are the signs and symptoms of chlamydia?

Most teenage girls who have chlamydia don’t show any symptoms. However, you might notice the following if you have chlamydia:

• slight increase/change in vaginal discharge
• the need to pass urine more often and/or pain on passing urine
• mild lower abdominal pain
• pain during sex
• irregular menstrual bleeding ( periods)
•  cystitis
• painful swelling and irritation in the eyes

Boys are more likely to notice symptoms than girls. These can include:

• discharge from the penis, which might be cloudy and stain underwear
• pain and/or a burning sensation when passing urine
• painful swelling and irritation in the eyes

However, you may not have any of these symptoms and still have chlamydia, or these symptoms could be mild and caused by other problems too. If you go to your GP with any of these symptoms, ask for a chlamydia test if you are not offered it. You are entitled to ask for it.  

How is chlamydia normally diagnosed and treated?

Testing for girls now involves either a urine sample or a swab that you insert into your vagina. The swab is then put in a special container and sent off to a laboratory for testing. For boys a urine sample is enough, although some clinics take swabs from inside the tip of the penis. This is because swabbing is often cheaper and can be more accurate.

Once chlamydia has been diagnosed, treatment is simple and effective. You will be given oral antibiotic tablets. If you are allergic to any antibiotics or you might be pregnant, it is important that you tell your doctor. This will affect the antibiotics you are given.

It is important that you finish any course of treatment. If you don’t finish, the infection may persist and you may have to start antibiotics again. If you are sexually active and have a partner, they will need to be treated too. Otherwise, you will be re-infected when you have sexual intercourse again.

Untreated Chlamydia can cause pelvic inflammatory disease (PID) in females. This can damage your Fallopian tubes (these take eggs from the ovaries to the womb) – they may even become blocked and stop working properly. This causes infertility (and Chlamydia is the biggest preventable cause of infertility in females). Chlamydia can also cause infertility in males as well as joint inflammation and swollen testicles.

When to ask for medical help

Because chlamydia is transmitted through sexual intercourse, if you are sexually active you are at risk. You are especially at risk if you do not use a condom every time you have sex (unless you and your partner have been tested and are clear) or if you have had several partners. But it’s not about how many people you’ve slept with – if you’ve had sex once without a condom, you are at risk. The problem is that because most of the time there are no symptoms, you don’t know you have it. The fact is that if you are under 20 and sexually active, you have more than a one in ten chance of having chlamydia.

What’s going to help?

Getting tested for chlamydia is the best thing to do if you have been sexually active.

Go to see a health advisor in a sexual health (GUM) clinic. You can find your nearest clinic by looking in the phone book or through NHS Direct (NHS 24 in Scotland). GPs are able to test for chlamydia as well as family planning clinics. School clinics can also provide testing. If you find it difficult to approach any of these you can always ask for a testing kit from your local pharmacy.

If you know you have chlamydia, you should try to encourage any ex-partners you have had to get tested – as they may have it too – even though they are showing no symptoms.

Can chlamydia be prevented?

Having unprotected sex can pass on chlamydia. The best way to stop chlamydia from being passed on during sex is to use condoms. These guard against STIs. Always use a condom with a new sexual partner and before you stop using them with that person, make sure you both get checked out by your local GUM clinic or GP.

Looking forward

When chlamydia is treated early on with antibiotics, the treatment is usually very effective and the infection clears up. However, if chlamydia is left undetected and untreated, again, it can cause serious health and fertility problems. This is why if you have taken any risks, testing for the infection is important – even if you feel perfectly healthy.

For more help and information

The fpa has plenty of advice. Visit them at www.fpa.org.uk.

There’s loads to read at www.ruthinking.co.uk.    

Last reviewed by Great Ormond Street Hospital: December 2007

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