| Introduction. Genital Chlamydia trachomatis and Neisseria gonorrhoeae are the two most prevalent bacterial sexually transmitted diseases in the world. Resource poor settings need inexpensive but accurate tests to identify infected persons for treatment. Through use of a pooling algorithm, i.e. testing specimens pooled and retesting specimens from positive pools individually, the cost of amplification-based tests could be minimized.; Methods. The accuracy and cost-savings of the pooling algorithm, when pooling four to ten specimens, for both C. trachomatis and N. gonorrhoeae by ligase chain reaction (LCR) was determined, and optimized for various population prevalences. Five female populations at risk for STDs in the Czech Republic and Slovakia were screened, including females attending a prenatal clinic (n = 134), an STD clinic (n = 100), and a high school (n = 233), a Gypsy population (n = 128), and sex workers (n = 35). Urine specimens were also tested for HIV-1 by EIA/Western Blot.; Results. The pooling algorithm for C. trachomatis testing was 98.4% to 100% sensitive and 100% specific. The pooling algorithm for N. gonorrhoeae testing was 95.8% to 100% sensitive when pooling and 100% specific. Using the pooling algorithm, the prevalence of chlamydia was 2.21% (0.5, 6.4 95% CI) in the prenatal clinic, 5.5% (1.8, 12.4 95% CI) in the STD clinic, 8.2% (3.6, 15.6 95% CI) in sexually active high school students, 22.9% (10.4, 40.195% CI) in street sex workers, and 3.9% (1.6, 6.6 95% CI) in Gypsies. Gonorrhea was found in two populations; 2.2% (0.3, 7.7 95% CI) in the STD clinic and 2.9% (0.1, 14.9) in street sex workers. Risk factors significantly associated with chlamydia infection included: >3 lifetime sex partners, >1 sex partner (last 3 months), genital discharge, and age <25 years. The pooling algorithm saved 65% of individual assay costs. No HIV infection was detected.; Conclusion. Using the pooling algorithm for C. trachomatis and N. gonorrhoeae testing by LCR in urine is accurate and significantly cost-saving for use in resource poor settings. The high chlamydia prevalence rates found in this study indicate the present need for screening and treatment programs in the Czech Republic and Slovakia. |
