Chlamydia is currently the most common STI in North America, with about 2.86 million reported cases each year in the United States alone. The Centers for Disease Control estimates that 1 in 15 sexually active girls aged 14 to 19 has chlamydia. Because infected individuals often display no symptoms, it is sometimes referred to as a ‘silent’ STI.

What the hell is it?

Chlamydia is a sexually transmitted infection caused by bacteria. It is most commonly found in sexually active teens and young adults ages 15 to 24, and is more common in women than in men. Chlamydia is transmitted through vaginal, anal, and oral sex.

Chlamydia infects the cervix, rectum, urethra, or (in some cases) all three.  It can occasionally infect the throat as well if passed on during oral sex. This STI can also spread to the eyes if you touch an infected area and then touch your eyes without first properly cleaning and disinfecting your fingers and hand.  Additionally, an infected mother may pass on chlamydia to her child if she gives birth vaginally.


Symptoms of chlamydia usually first appear within two days to three weeks of contracting the infection. However, most people will not notice any symptoms at all.

  • Women with chlamydia may experience burning while peeing, abnormal vaginal discharge, bleeding between periods, increased pain during periods, pain during sex, abdominal pain, lower back pain, fevers or chills, discharge from the anus, and painful bowel movements.
  • Men with chlamydia may experience burning while peeing, itching of the penis, discharge from the penis, redness of the penis, pain or swelling of the testicles, discharge from the anus, and painful bowel movements.

Treatment Options

Chlamydia is easy to cure if treated early on; the treatment consists (in most cases) of a single dose of oral antibiotics.  If your healthcare provider prescribes you more than one dose, it is important to take ALL of the antibiotics given to you, even if your symptoms have already disappeared. It is best to wait one week after treatment to have sex again to ensure you do not still have the infection in your system.  Once chlamydia has been successfully treated, you can longer transmit the disease to your partner(s), however, you are still at risk to contract it again in the future.  Although treatment will fully cure chlamydia itself, it will not affect any other damage caused by the disease, which is why it it is so important to be tested regularly and obtain treatment as soon as possible.

When not treated in a timely manner, chlamydia can lead to gallbladder infection or pelvic inflammatory disease in women, causing severe pain and infertility.  In men, untreated chlamydia can lead to swelling of the prostate, urethral inflammation, and occasionally infertility.


Chlamydia is best prevented by using condoms during any kind of sexual intercourse (This means during anal sex and oral sex too!) You can also use dental dams to protect against chlamydia during oral sex. As always, it is important to be tested regularly for STIs. This is especially important in the case of chlamydia, as it often shows no symptoms.

Fun Fact

Chlamydia is also perhaps the only STI you can contract through cuddling- but you’d have to be cuddling a koala! Sadly, many koalas have chlamydia and it is one of several factors contributing to their status as an endangered species. Koalas contract a different strain of chlamydia which, among the marsupials, is not always passed on sexually and is much more dangerous to them. If a koala happens to pee on you, especially if you have any open cuts, it is a good idea to get tested for chlamydia just in case.  Koala to human transmission of chlamydia is extremely rare but still possible.


Learn more about STIs in our series here.



Detailed STD Facts – ChlamydiaCenters for Disease Control. Centers for Disease Control, 29 November 2012. Web. 30 July 2014.

Chlamydia. Saskatchewan Health. Government of Saskatchewan, September 2011. Web. 13 July 2013.

Chlamydia. Canoe Health. MedBroadcast Clinical Team, 2014. Web. 13 July 2014.

Bacterial STIs-STDs. Sexuality and U. The Society of Obstetricians and Gynaecologists of Canada, 2012. Web. 13 July 2014.

Koala chlamydia: The STD threatening an Australian icon. BBC News. Ari Daniel Shapiro, 24 April 2013. Web. 13 July 2014.