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Chlamydia

Genital Chlamydia trachomatis infection is the most commonly diagnosed bacterial sexually transmitted infection in genitourinary medicine (GUM) clinics in the United Kingdom. The number of diagnoses of uncomplicated genital chlamydial infection in GUM clinics has risen steadily since the mid-1990s. The prevalance is highest in sexually active adults, especially women aged 16 to 24 years and men aged 18 to 29 years. As most people are asymptomatic, large proportions of cases remain undiagnosed. Untreated genital chlamydial infection may have serious long-term consequences, especially in women in whom it is a well-established cause of pelvic inflammatory disease (PID), ectopic pregnancy and infertility. The annual cost of chlamydia and its consequences in the United Kingdom is estimated to be more than £100 million.