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Sexually transmitted infection rate

Sexually Transmitted Infections (STI) are measured as the chlamydia incidence (number of new cases reported) per 100,000 population.

Measure Tabs


Reason for Ranking

Chlamydia is the most common bacterial STI in North America and is one of the major causes of tubal infertility, ectopic pregnancy, pelvic inflammatory disease, and chronic pelvic pain.[1,2] STIs are associated with a significantly increased risk of morbidity and mortality, including increased risk of cervical cancer, infertility, and premature death.[3] STIs also have a high economic burden on society. The direct medical costs of managing sexually transmitted infections and their complications in the US, for example, was approximately 15.6 billion dollars in 2008.[4]

Measurement Strengths and Limitations

Chlamydia incidence rates are associated with unsafe sexual activity. Chlamydia rates are readily available and reliable for nearly all counties. An important caveat in chlamydia rate reporting is that increases in reported infections may reflect true increases in disease, but may also reflect expanded screening, use of increasingly sensitive diagnostic tests, increased emphasis on case reporting from providers and laboratories, and improvement in the information systems for reporting. Communities with poor screening rates may have artificially low rates of chlamydia incidence. Finally, chlamydia is only one of many STIs.

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