Chlamydia
In this condition factsheet:
The Facts on Chlamydia
Chlamydia is the most commonly reported bacterial sexually transmitted infection (STI) in Canada, affecting youths and young adults most often, with young women (15 to 24 years) having the most reported cases.
The infection is named after the bacterium that causes it, Chlamydia trachomatis. Most women and many men who are infected with the bacteria have no symptoms and therefore don't know they have chlamydia.
Chlamydia is easily treated, but it can sometimes lead to serious complications if it isn't caught early enough. It is estimated that up to 40% of untreated women will develop symptomatic pelvic inflammatory disease (PID), which can be very painful. The risk of preterm delivery, ectopic pregnancy, or infertility also increases with an untreated chlamydia infection.
Screening for chlamydia is routine for women who are under 25 years old, have a history of a prior sexually transmitted infection, engage in high-risk sexual behavior, or are pregnant. Men are not routinely screened for chlamydia unless they have sex with men or live in an area where there are many cases of chlamydia.
Causes of Chlamydia
Chlamydia is spread during sexual contact and is highly infectious. It can be transmitted through vaginal, anal, or oral sex. Ejaculation does not have to occur for chlamydia to be spread.
Newborn babies can get infected if their mothers have chlamydia. Nearly half of infants born vaginally (i.e., not by caesarean) to infected mothers will contract chlamydia during delivery. In newborns, chlamydia infections appear as eye problems or respiratory problems rather than the typical genital infections seen in adults.
Symptoms and Complications of Chlamydia
People with chlamydia don't always have symptoms. It is estimated that more than 70% of women and 50% of men won't show signs of infection. If symptoms start, they will generally show up within 1 to 3 weeks after exposure, but can take as long as 6 weeks to appear. It can infect genital tracts including the cervix, uterus, fallopian tubes, urethra, and epididymis (tube that the stores and carries sperm), as well as the throat, rectum, and eyes.
In men, chlamydia usually starts in the urethra. Symptoms often come and go, or might only be noticed during the first urination of the day. These include:
- painful burning on urination
- redness, swelling, burning, and itching around the opening of the penis
- discharge from the penis, usually milky-white, grey, or yellow in colour
- pain in the scrotum
- inflammation of the coiled tube (epididymis) at the back of the testicle that stores and carries sperm, called epididymitis. This will cause testicular pain, tenderness and swelling.
- prostatitis, an inflammation of the prostate
- sterility if the infection spreads from the urethra to the testicles
In women, chlamydia usually begins on the cervix. While symptoms are rare in women, they can include:
- a yellowish vaginal discharge that might have a foul odor
- painful burning during urination
- bleeding between periods and after intercourse
- pain during vaginal intercourse
- pain in the lower abdomen
- pelvic inflammatory disease (PID), a serious condition that can permanently damage the fallopian tubes, uterus, and ovaries (this can cause infertility, ectopic pregnancy and chronic pain)
Chlamydia can cause a number of complications in both men and women, depending on the infected site, including:
- conjunctivitis (pinkeye)
- pharyngitis (sore throat)
- rectal pain, bleeding, and discharge
- reactive arthritis (formerly called Reiter's syndrome), a type of arthritis that can damage the joints and eyes
In infants with chlamydia, eye infections occur in about 20% to 50% of babies born to infected mothers, and the infection usually occurs within 2 weeks of delivery. If the infection isn't treated in time, it can lead to scarring of the cornea and permanent damage to vision. About 5% to 30% of babies born to infected mothers will get pneumonia, usually within 2 to 12 weeks after delivery. The chlamydial pneumonia can cause anything from mild symptoms to breathing problems that include a repetitive cough.
