Chlamydia: Why Testing Matters When There Are No Symptoms

Chlamydia is the most frequently reported bacterial sexually transmitted infection in most of Europe and North America, and the reason it spreads so effectively is simple: most people who have it feel completely well. This is a plain, non-alarmist overview of how it presents, how it is found, and how it is treated.

Most cases have no symptoms

The majority of infections cause nothing noticeable at all. When symptoms do appear, they are usually mild and easy to attribute to something else: unusual discharge, discomfort passing urine, bleeding between periods or after sex, or pain in the lower abdomen or testicles. Because “feeling fine” is the normal presentation, symptoms are a poor guide to who should test.

Why it is worth finding

Untreated, chlamydia can ascend to the upper reproductive tract. In women this can cause pelvic inflammatory disease, which is associated with chronic pelvic pain, ectopic pregnancy and tubal infertility. In men it can cause epididymitis. These outcomes are uncommon relative to the number of infections, but they are largely preventable, and prevention depends entirely on testing rather than waiting for symptoms.

Testing is straightforward

Diagnosis uses a nucleic acid amplification test, which in practice means a urine sample or a swab that you can often take yourself. Many countries offer free postal testing kits through their sexual health services. Testing is generally recommended annually for sexually active people under 25, and after any change of partner at any age.

Treatment

Chlamydia is treated with a short course of antibiotics and the cure rate is high. Two points do the practical work:

• Finish the course, and avoid sex until it is complete plus whatever interval your clinician specifies.
• Partners need testing and treatment too. Reinfection from an untreated partner is the most common reason people test positive again a few months later. Clinics can notify partners anonymously if that is easier.

A repeat test a few months after treatment is often advised, not because the antibiotics failed but because reinfection is common.

Reducing the risk

Condoms substantially reduce transmission. Regular testing does not prevent infection, but it shortens how long an undetected one persists, which is what most of the harm depends on. Our general health section covers routine screening more broadly.

This article is general information, not medical advice. If you think you may have been exposed, contact a sexual health service or your doctor: testing is quick, usually free, and routinely confidential.