<P> At present, the NAATs have regulatory approval only for testing urogenital specimens, although rapidly evolving research indicates that they may give reliable results on rectal specimens . </P> <P> Because of improved test accuracy, ease of specimen management, convenience in specimen management, and ease of screening sexually active men and women, the NAATs have largely replaced culture, the historic gold standard for chlamydia diagnosis, and the non-amplified probe tests . The latter test is relatively insensitive, successfully detecting only 60--80% of infections in asymptomatic women, and often giving falsely positive results . Culture remains useful in selected circumstances and is currently the only assay approved for testing non-genital specimens . Other method also exist including: ligase chain reaction (LCR), direct fluorescent antibody resting, enzyme immunoassay, and cell culture . </P> <P> Prevention is by not having sex, the use of condoms, or having sex with only one other person, who is not infected . </P> <P> For sexually active women who are not pregnant, screening is recommended in those under 25 and others at risk of infection . Risk factors include a history of chlamydial or other sexually transmitted infection, new or multiple sexual partners, and inconsistent condom use . For pregnant women, guidelines vary: screening women with age or other risk factors is recommended by the U.S. Preventive Services Task Force (USPSTF) (which recommends screening women under 25) and the American Academy of Family Physicians (which recommends screening women aged 25 or younger). The American College of Obstetricians and Gynecologists recommends screening all at risk, while the Centers for Disease Control and Prevention recommend universal screening of pregnant women . The USPSTF acknowledges that in some communities there may be other risk factors for infection, such as ethnicity . Evidence - based recommendations for screening initiation, intervals and termination are currently not possible . For men, the USPSTF concludes evidence is currently insufficient to determine if regular screening of men for chlamydia is beneficial . They recommend regular screening of men who are at increased risk for HIV or syphilis infection . </P>

Where did the first case of chlamydia come from