Causes of Chlamydia

Bhavna Singh   by Bhavna Singh, MS, Biotechnology    Last updated on September 26, 2019,

causes of chlamydia


How is chlamydia caused?

Chlamydia, a sexually transmitted disease is caused by Chlamydia Trachomatis bacteria. When an infection is present, this bacterium resides in the cervix, vagina, urethra and rectum of the infected person.  Apart from these organs, it can also survive in the eyes and throat of a person. Any type of sexual contact with an infected person can spread this infection.

Chlamydia, like other sexually transmitted infections (STIs), spreads through sexual activities. It is passed during contact with the penis, vagina, mouth or anus of an infected person. Ejaculation does not have to occur to acquire the chlamydial infection.

Chlamydia can transmit when the soft inner covering of openings in the human body (mucosal membrane) comes in contact with mucous secretions of an infected person. This can happen during unprotected sex (vaginal or anal).

Oral sex is not so common cause of this infection. Chlamydia is unlikely to be transmitted during oral sex as the bacterium Chlamydia Trachomatis prefers to target genitals in comparison to mouth and throat. This reduces the chances of Chlamydia being transmitted by mouth-to-mouth or genital-to-mouth contact. However, the chances cannot be ignored completely.

Chlamydia does not require penetration to get transmitted. If genital, rectum and mouth come in contact with the infected secretions or fluids, transmission is possible.

Wiping the infected genital area with toilet paper may spread the infection to the rectal area. Thus, if the person has not had anal sex, still there are chances of developing chlamydia infection in rectum. Chlamydia, however, is not passed through things like shaking hands or sharing toilet seats.

Eye infections from Chlamydia may be a result of using infected person's towel directly. The person may also get Chlamydia in eyes by any other way by which genital discharge reaches eyes like rubbing eyes after having sex etc.

Chlamydia can also occur perinatally (before birth) from an untreated mother to her baby during childbirth. In severe cases, it results into ophthalmia neonatorum (conjunctivitis) or pneumonia in infants. Rectal and genital chlamydial infections sometimes persist for more than a year in infants infected at birth.

Young and sexually active people are at high risk. There is a possibility of child abuse in the cases of pre-pubertal (or adolescent) children with vaginal, urethral or rectal infections.

Even after a person has been treated for chlamydia, it is possible to get the infection again. With chlamydia, repeated infections are common. Read about treating of Chlamydia infection.

Who is at risk?

Any person who is sexually active can acquire this infection. Chlamydia is very common in young people. According to a survey, 1 in 20 sexually active young women has Chlamydia.

Following are the reasons that make a person more prone to develop this infection:

  • unprotected sex (without condoms)
  • polygamous relationship (sex with multiple partners)
  • not using dental dams while having oral sex
  • prior history of chlamydia or any other sexually transmitted disease

Sexually active people in some areas are at a high risk of acquiring Chlamydia because of cultural, biological and behavioral reasons. Men who have intercourse with men are also at high risk for Chlamydia infection as it can be transmitted by oral or anal sex. 

When to see a doctor?

Chlamydia infection leads to severe complications when left untreated. Pelvic inflammatory disease (PID) is a serious medical condition that leads to infertility in females. Read about Chlamydia complications.

Women with severe abdominal pain and abnormal vaginal discharge (yellow or green) should immediately see a doctor. Fever, painful urination and abnormal discharge from genitals may show an infection. Inflammation in testicles should not be ignored. Men with these symptoms should immediately refer a doctor.  Read about signs and symptoms of Chlamydia.

Bhavna Singh

Bhavna Singh is a biotechnologist with a special interest in molecular biology, genetic engineering, recombinant DNA technology, and biochemistry. She pursued her Master’s degree in Biotechnology from Gautam Buddha University, Greater Noida. Bhavna has also worked as a Research Fellow at Indian Agricultural Research Institute (IARI), New Delhi.

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