Chlamydia is a common sexually transmitted infection (STI) caused by the bacterium Chlamydia trachomatis. Globally, there were an estimated 128.5 million new chlamydia infections among adults aged 15-49 in 2020. While treatable with antibiotics, getting reinfected with chlamydia is a significant and frequent concern.
Understanding Chlamydia Reinfection
Chlamydia reinfection occurs when an individual contracts the infection again after being successfully treated and cleared of a previous infection. This differs from an initial infection or a persistent, untreated infection, as it signifies a new exposure to the bacterium. Reinfection is a common occurrence, with some reports indicating that roughly 20% of females treated for chlamydia experience reinfection within six months.
A major reason for reinfection is the often asymptomatic nature of chlamydia. Many people (50% to 70%) experience no noticeable symptoms, which can lead to unknowingly spreading the infection. This contributes to higher rates of transmission and reinfection.
How Reinfection Occurs
Reinfection with chlamydia primarily happens through sexual contact with an infected partner. The most frequent cause is an untreated sexual partner from a previous encounter, who can re-expose the previously treated individual to the bacterium.
A person can also become reinfected by contracting chlamydia from a new sexual partner. Knowing the sexual health status of new partners is important. Additionally, not completing the full course of prescribed antibiotics can lead to a persistent infection, which may be mistaken for reinfection.
Preventing Reinfection
Preventing chlamydia reinfection requires a multi-faceted approach, with partner notification and treatment being a key strategy. All sexual partners from the past 60 days of diagnosis should be evaluated, tested, and presumptively treated for chlamydia to break the chain of transmission.
Consistent and correct use of barrier methods, such as condoms, significantly reduces the risk of chlamydia transmission and reinfection during sexual activity. Individuals should abstain from sexual intercourse for seven days after single-dose therapy or until completion of a seven-day regimen and resolution of symptoms.
Regular testing is important, particularly for sexually active individuals. The Centers for Disease Control and Prevention (CDC) recommends retesting approximately three months after treatment, regardless of whether partners were treated. If a three-month retest is not feasible, retesting is recommended whenever individuals next seek medical care within 12 months of initial treatment. Open communication with sexual partners about health status and testing is also encouraged to facilitate mutual prevention.
Health Impact of Reinfection
Repeated chlamydia infections can lead to serious short-term and long-term health consequences, particularly for women. A significant risk is Pelvic Inflammatory Disease (PID), an infection of the uterus, fallopian tubes, or ovaries. Repeated infections increase the risk and severity of PID, which can cause scarring inside the reproductive organs.
This scarring from PID can lead to tubal factor infertility, making it difficult for an egg to be fertilized or for a fertilized egg to implant. Repeated chlamydia infections also elevate the risk of ectopic pregnancy, a life-threatening condition where a fertilized egg implants outside the uterus, typically in the fallopian tube. Women may also experience chronic pelvic pain as a long-term complication. For men, untreated chlamydia, including reinfections, can cause epididymitis, an inflammation of the tube that carries sperm from the testicles, which can lead to pain, swelling, and in rare cases, sterility. Chlamydial infection can also increase susceptibility to HIV transmission or acquisition.