Overview

Chlamydia trachomatis causes the most cases of sexually transmitted infections and is the main cause of blindness worldwide.¹ Chlamydia is a prevalent sexually transmitted infection that can be found in both males and females. The cause of it is a bacterium known as Chlamydia trachomatis. It can be easily managed and cured using antibiotics. If left untreated, chlamydia can lead to severe issues such as infertility and ectopic pregnancy. In pregnant females, it has the potential to result in the premature birth of the infant. Using condoms correctly and consistently during sexual activity is the best method to avoid chlamydia.²

The cervix is the most frequent anatomic location of infection in women. This can manifest as cervicitis, urethritis, pelvic inflammatory disease, perihepatitis, or proctitis. Chlamydial infections in women, particularly when left untreated, can raise the risk of infertility and ectopic pregnancy, resulting in significant medical expenses. Additionally, there are potential risks associated with having an infection while pregnant. Furthermore, babies delivered through the birth canal from mothers who have genital Chlamydia trachomatis may experience conjunctivitis or pneumonia.¹

Risk factors

Individuals under 25 are more likely to contract chlamydia compared to those who are older. This is because the younger population is more prone to having multiple risk factors.³

Factors that increase the likelihood of contracting chlamydia are:

1. Failure to use a condom or improper condom usage
2. Reduced utilisation of healthcare services to avoid and manage sexually transmitted infections
3. Having new or multiple sexual partners
4. Switching sexual partners without knowing about a chlamydia infection

Causes

Chlamydia is caused by bacteria. Bacteria are typically transmitted through sexual activity or exposure to infected genital fluids (semen or vaginal fluid).⁴ Chlamydia can be transmitted via:

1. unprotected intercourse through the vagina, anus, or mouth
2. Sharing unwashed sex toys without using a new condom for each use
3. Coming into contact with your partner's genitals with your own can result in chlamydia, even without penetration, orgasm, or ejaculation
4. Contracting the virus through contact with contaminated semen or vaginal fluid entering your eye
5. A pregnant female has the ability to transmit it to her infant

Casual contacts like kissing, hugging, sharing baths, towels, swimming pools, toilet seats, or cutlery cannot transmit Chlamydia.

How common is chlamydia?

Chlamydia is the most prevalent STI that is bacterial STI. Roughly 1.5 million instances of chlamydia are documented annually. The number of infections is probably even greater. Many instances of chlamydia do not show any symptoms, indicating the presence of an infection without any visible signs or indications. A large number of these incidents probably need to be reported.

Specific demographic traits (such as age, gender, and race) can increase the likelihood of being diagnosed with chlamydia.⁵ Individuals who have a higher likelihood of contracting chlamydia are:

1. An adolescent or young person between the ages of 15 and 24. This age group accounts for over 50% of all reported chlamydia cases in the U.S. The percentage is greater for females or individuals designated female at birth (AFAB). Providers typically suggest screening for chlamydia in individuals assigned female at birth who are aged between 15 and 24 years old
2. A male individual who engages in sexual activities with other men (MSM). Chlamydia infections are more common among men or individuals assigned male at birth (AMAB) who engage in sexual activity with other men or partners AMAB, as opposed to those who have sexual relations with women or individuals AFAB
3. African American and not of Hispanic descent. Chlamydia infections disproportionately impact non-Hispanic Black populations

Increased transmission rates in specific communities are more about connections and limited access to resources for preventing STIs, rather than sexual activities. For instance, chlamydia is more prone to spreading among individuals in communities with elevated infection rates. It is more probable to be transmitted within communities lacking convenient access to sexual education or protective measures such as condoms and dental dams. The CDC advises getting tested for chlamydia as part of your routine health care.

Symptoms

Typically, chlamydia does not show any signs or symptoms. It can infect the cervix and subsequently spread to the uterus and fallopian tubes, leading to:⁶

1. Pelvic inflammatory disease (PID)
2. Chronic pelvic pain
3. Ectopic pregnancy
4. Infertility

When women have symptoms of chlamydia, they may seem similar to those of other conditions, such as a UTI.⁷ Symptoms may include:

1. Abnormal vaginal discharge that is white, yellow, or grey
2. Strong-smelling vaginal discharge may be present
3. A feeling of itchiness or a sensation of burning in or near the vaginal area
4. Discharge resembling pus found in the urine
5. Discomfort, irritation, or a sensation of heat during urination
6. Discomfort during intercourse caused by the infection increases sensitivity in the cervix
7. Blood loss following intercourse
8. Abnormal bleeding occurs in the middle of menstrual cycles and may appear as red, brown, or pink
9. Abdominal pain that is either cramping, dull, or sharp

Signs of chlamydia in different body regions

Chlamydia can be contracted by both males and females through engaging in receptive anal sex. It can also be transmitted from another infected area, such as the vagina. Signs and symptoms consist of:

1. Discharge
2. Pain in the rectum
3. Bleeding

Coming into contact with infected genital fluid can lead to chlamydial conjunctivitis and trachoma, a potential cause of blindness, in the eyes. Signs of a possible illness consist of:

1. Irritability
2. Puffy eyelids
3. Eye redness
4. Discharge
5. Teary eyes
6. Enlarged lymph glands near the eyes
7. Sensitivity to light is heightened in photophobia

Infections with chlamydia can be transmitted to the throat through oral sex. Typically, individuals with chlamydia in their throat are asymptomatic, but if they do have symptoms, it's commonly just a sore throat. Additional signs may consist of:

1. Enlarged tonsils
2. Pain in the mouth
3. The presence of redness within the oral cavity
4. Elevations on the tongue
5. The tonsils or the back of the throat have white spots
6. Slight increase in body temperature
7. Tiredness
8. Enlarged lymph glands in the neck
9. Ulcers near the mouth

Diagnosis

Molecular tests, whether conducted in a lab or at the point of care, are considered the most reliable method for diagnosing C. trachomatis. Several speedy diagnostic tests are on the market, but they are currently not as effective as molecular tests.²

Sexual history evaluation and risk assessment are vital before making a diagnosis. Clinical examination, along with speculum examination and palpation, can offer valuable indications for clinical diagnosis.

A syndromic approach for managing cases is suggested in primary healthcare settings lacking diagnostic capabilities for identifying C. trachomatis.

Urine samples are frequently employed for nucleic acid amplification test (NAAT) but have lower sensitivity compared to swab-collected samples from genital (vaginal or urethral), anal, and oropharyngeal sites. The sampling of specimens from various areas of the body is influenced by sexual behaviours and past medical experiences. Self-collection of samples is suggested because the test results are comparable to those obtained by a healthcare provider.

Regular testing is recommended for individuals at higher risk of chlamydial infection, like female sex workers, to prevent complications and spread due as most cases are asymptomatic.

It is advisable to conduct tests for other sexually transmitted infections, such as HIV, syphilis, and gonorrhea, in addition to chlamydia testing, while also notifying sexual partner(s).

A particular molecular test is required for LGV diagnosis.

Treatment

Chlamydia is generally easily treatable with antibiotics. You might receive a prescription for either Doxycycline to be taken daily for a week or Azithromycin to be taken once a day for 3 days. If you are taking Doxycycline, it is advised to avoid any sexual activity (including oral sex) until both you and your current sexual partner have completed the treatment. Wait at least a week after treatment with Azithromycin before engaging in any sexual activity, including oral sex.

It is crucial that your present sexual partner and any other recent sexual partners also get tested and treated to prevent the infection from spreading.

Individuals under the age of 25 diagnosed with chlamydia should be provided with the opportunity to undergo a follow-up test 3 to 6 months post-treatment. This is because young adults who are diagnosed with chlamydia are more likely to get infected again.

Sexual health or genitourinary medicine (GUM) clinics can assist you in reaching out to your sexual partners. The clinic or you can communicate with the, or a note can be sent to advise them to get tested. The confidentiality of your identity will be safeguarded as the note will not contain your name.⁵

Prevention

1. The sole method to prevent chlamydia is to refrain from engaging in vaginal, anal, or oral intercourse with someone infected with chlamydia. Make sure that any sex toys contaminated with bacteria do not touch your genitals⁵
2. It can be difficult to determine if a current or potential partner has chlamydia, as many individuals with the infection may not experience any symptoms. Keeping safe sex practices a consistent part of your sexual routine can help prevent negative outcomes
3. Ensure to use condoms for vaginal, anal, and oral intercourse
4. Utilise dental dams when engaging in oral sex or genital-to-genital contact
5. If you must share sex toys, make sure to clean them after each use and put a condom on toys used for penetration
6. Engage in sexual activity with just one partner, who is also exclusive to you

Summary

Chlamydia trachomatis is a prevalent sexually transmitted infection caused by a bacterium that can result in severe health problems if not treated. It can impact both men and women, with the cervix being the most frequent location of infection in females. Chlamydia can be effectively treated and cured using antibiotics, but if left untreated, it may lead to issues like infertility, ectopic pregnancy, and premature birth. The highest occurrence of the infection is seen in people under 25 years old and it can spread through unprotected sex or contact with infected genital fluids. It is advised to engage in routine testing and practice safe sex, which includes always using condoms, to prevent the spread of infections. It is crucial to undergo regular testing if you are at an increased risk of chlamydia infection, as symptoms may not always be noticeable. The usual treatment includes taking antibiotics, and it is crucial for both you and your sexual partners to get treated to stop the infection from spreading.