Chlamydia – A Detailed Fact Sheet

Sexually transmitted infections (STIs) are communicable diseases that are transmitted with sexual contact. Chlamydia is the most common communicable disease in Australia with people under 30 years of age at the highest risk. We’ve put together a comprehensive fact sheet to give you a good overview. Please use this to supplement information you receive from your General Practitioner.

What is chlamydia?

Chlamydia is a Sexually Transmitted Disease (STD) caused by infection with a bacterium called Chlamydia trachomatis. It affects pelvic organs. In women, it can cause cervicitis (infection of the cervix), and in both men and women, it can cause urethritis (infection of the urethra) and proctitis (infection of the rectum).

If left untreated, it can lead to multiple complications, especially in women, including pelvic inflammatory disease (PID), tubal factor infertility, ectopic pregnancy, and chronic pelvic pain. In men, it can progress and cause swelling and pain in one or both testicles but this complication is rare.

Incidence of chlamydia in Australia

Chlamydia is the most common sexually transmitted disease in Australia and worldwide, in both men and women. About 97,000 men and women are diagnosed with chlamydia each year. It is the leading cause of proctitis among homosexual men worldwide. ¹ The numbers are just as high in women. During 2017-18, about 52,318 cases of chlamydia were reported in women. Of all the cases of sexually transmitted infections, 52% were chlamydial infections. The rate of infection was 442 per 100,000 with 20-24 year-olds being the age group with the highest infection rate. ²

How do you get chlamydia?

A person infected with chlamydia can transmit the disease to their partner via sexual contact that includes contact with their penis, vagina, mouth, or anus. The transmission or acquisition of chlamydia does not require ejaculation. It can simply propagate via contact.

The infection can also spread perinatally when an untreated pregnant woman gives birth to an untreated baby. In some cases, an untreated baby can develop conjunctivitis or pneumonia due to chlamydial infection. Chlamydial conjunctivitis has been reported in 18-44% of children born to mothers with untreated chlamydial cervical infection at the time of delivery, and chlamydial pneumonia in 3-16% of them.

You can also get chlamydia from oral sex with a person who is infected with chlamydia. Thus, opting for oral sex does not offer protection and people who prefer oral sex are also at risk and can contract chlamydial infection. ¹

Having chlamydial infection once does not offer immunity. If a person who has been treated for chlamydia has sexual contact with an infected person, they may get infected again.

What are the symptoms of chlamydia?

Chlamydia can affect men, women and infants. The symptoms may vary depending upon the organ affected by the infection.

Chlamydia symptoms in women

Chlamydia can affect multiple sexual organs in women and the manifestations correspond to the organs involved.

Cervicitis:  It is the inflammation of the cervix. About 70% of women will have no symptoms, or have only mild symptoms such as white, yellowish or strong smelling vaginal discharge, bleeding, abdominal pain, and painful urination. The classic presentation of mucopurulent cervicitis with discharge and uncontrollable bleeding is found only in a minority of women. Post-coital bleeding and intermenstrual bleeding is also reported by some women. ³

Pelvic inflammatory disease (PID): When C. trachomatis ascends to the upper reproductive tract and involves the uterus, fallopian tubes and ovaries, it causes pelvic inflammatory disease. The patient may generally experience abdominal or pelvic pain, and may also show signs and symptoms of cervicitis. Additionally, there may be nausea, vomiting, fever, chills, lower back pain, pain during intercourse, painful; urination, and  bleeding after sex. ⁴

Urethritis: In women, chlamydial infection of the urethra (the canal that carries urine from the bladder to the outside of the body) is less common than in men. Symptoms can include frequent urination and dysuria (pain while urinating), which can be mistaken for urinary tract infection (UTI).

Proctitis: Even though proctitis is more common in men, it can also develop in women. The symptoms may include rectal pain, discharge, or bleeding during anal intercourse. In other cases, the anal and rectal infection can be asymptomatic, depending upon the subtype of chlamydial bacteria causing disease.

Perihepatitis: This condition can occur when an infection with chlamydia involves the outer covering of the liver called the capsule and the lining of the abdomen called the peritoneum. It is also known as Fitz Hugh Curtis syndrome.

Patients with the pelvic inflammatory disease most often experience this syndrome as well. It is associated with pain in the right upper abdomen or pleuritic pain (sharp pain in the chest). In contrast to other conditions that also affect the liver or cause right upper quadrant pain, abnormal liver enzyme levels are rare in chlamydia induced perihepatitis. ⁵

Chlamydia symptoms in men

In men, the penis and anus are the most commonly affected organs.

Urethritis: It is the inflammation of the urethra (the tube that carries urine from the bladder to the outside). Men are more likely to suffer from urethritis.

While there are subtle differences in clinical presentation between gonococcal and chlamydial urethritis, no reliable distinction can be made without testing.

The condition is typically characterized by dysuria (pain while urinating) and urethral discharge, which may be white, grey, or clear.

Epididymitis: It is the inflammation of the epididymis. The epididymis is a long, coiled tube that stores and transports sperms. Symptoms of epididymitis include unilateral testicular pain and tenderness, palpable swelling of the epididymis, and fever. Hydrocele (fluid in the scrotum), and swelling and pain of the scrotum are also possible in rare cases.

Prostatitis: It is the inflammation of the prostate. The prostate is a gland present in close proximity to the bladder in men. Dysuria (pain while urinating) and urinary dysfunction are common symptoms of prostate infection, as are pelvic pain and difficulty ejaculating. When examined under a microscope, prostate secretions may demonstrate increased leukocyte (white blood cells) counts.

Proctitis:  Chlamydial infection of the anus and rectum can be asymptomatic or present with rectal pain, discharge, or bleeding during anal intercourse.

When do chlamydia symptoms appear?

Symptoms of the disease do not appear as soon as you are infected. It requires a certain duration for the pathogen to divide sufficiently and infect enough cells to produce symptoms.  This period between the time of infection and the appearance of symptoms is called the “incubation period”.

The incubation period for chlamydia is 5 to 14 days following infection. ⁶

What are the complications of chlamydia?

If left untreated, chlamydia can lead to serious complications, particularly in women.

Pelvic inflammatory diseases (PID)

In women, untreated chlamydia can spread to the uterus, fallopian tubes and ovaries, leading to pelvic inflammatory disease (PID). Affected women with untreated chlamydia are about 10 to 15 per cent likely to experience symptomatic PID.

Ectopic pregnancy

Chlamydia can cause ectopic pregnancy (implantation of a fertilized egg in locations other than the uterus, fallopian tubes and ovaries being the most common ones) which is a medical emergency and requires immediate treatment.

Infertility

Chlamydia causes scarring and inflammation of the fallopian tubes which can lead to infertility.

Reactive arthritis

Symptomatic or asymptomatic chlamydial infection can result in reactive arthritis in both men and women, sometimes as a part of a triad of symptoms (conjunctivitis, arthritis and urethritis), called Reiter’s syndrome. ⁸

Complications in pregnancy

Chlamydia in pregnancy has been associated with an increased risk of pre-term delivery. It also causes conjunctivitis and pneumonia in neonates.

How to test for chlamydia?

Testing for chlamydia is performed by taking a sample for culture, using a swab.

In women, the sample is taken from the vagina.

In men, the sample is taken from the urethra using a swab.

The sample culture is then seen under a microscope to check for the presence of the pathogen C. trachomatis.

What is the treatment for chlamydia?

Both partners should be treated for chlamydia even if only one of them is diagnosed with the infection. Your doctor will consider Chlamydia treatment with a course of oral treatment.

After treatment, how long do you have to avoid sex?

Sexual intercourse should be avoided during the treatment. If you have received a single dose of medicine, you should avoid sex for at least 7 days following the dose. If you are receiving a 7-day treatment, you should wait till you have completed the course of your treatment. ¹

Bibliography

1. Chlamydia – CDC Fact Sheet (Detailed). Available from https://www.cdc.gov/std/chlamydia/stdfact-chlamydia-detailed.htm#_ENREF_1
2. The health of Australia’s females. Available from https://www.aihw.gov.au/reports/men-women/female-health/contents/how-healthy/sexual-health
3. Detels, R., Green, A. M., Klausner, J. D., Katzenstein, D., Gaydos, C., Handsfield, H., Pequegnat, W., Mayer, K., Hartwell, T. D., & Quinn, T. C. (2011). The incidence and correlates of symptomatic and asymptomatic Chlamydia trachomatis and Neisseria gonorrhoeae infections in selected populations in five countries. Sexually transmitted diseases, 38(6), 503–509.
4. Pelvic inflammatory disease. (2012). American family physician, 85(8), 797–798.
5. Mohseni M, Sung S, Takov V. Chlamydia. [Updated 2021 Aug 11]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK537286/
6. William M. Geisler, Duration of Untreated, Uncomplicated Chlamydia trachomatis Genital Infection and Factors Associated with Chlamydia Resolution: A Review of Human Studies, The Journal of Infectious Diseases, Volume 201, Issue Supplement_2, June 2010, Pages S104–S113, https://doi.org/10.1086/652402
7. Rours, G.I.J.G., Duijts, L., Moll, H.A. et al. Chlamydia trachomatis infection during pregnancy associated with preterm delivery: a population-based prospective cohort study. Eur J Epidemiol 26, 493–502 (2011). https://doi.org/10.1007/s10654-011-9586-1
8. Kobayashi, S., & Kida, I. (2005). Reactive arthritis: recent advances and clinical manifestations. Internal medicine (Tokyo, Japan), 44(5), 408–412. https://doi.org/10.2169/internalmedicine.44.408