ObjectivesThe aims of the study are to investigate the distribution and frequency of different sexually transmitted diseases (STDs) among a large study population of individuals undergoing STD investigation both in inpatient and STD clinic settings and to evaluate influence of test anonymity on the positivity rate of pathogens.Material and MethodsA retrospective study retrieved epidemiologic data from the following 3 sources: a secondary referral hospital and 2 STD clinics in Northern Israel. Positivity rate of Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), Mycoplasma genitalium, and Trichomonas vaginalis (TV) was assessed and stratified based on age, sex, site of sampling, and anonymity of test. Adjusted odds ratios (ORs) were calculated by multivariable logistic regression.ResultsOverall, 3,753 assays were performed on 2,407 patients who were screened for STD. Chlamydia trachomatis (4.8%) was the most frequently detected STD, followed by NG (2.1%), MG (1.9%), and TV (0.6%). Mycoplasma genitalium (OR, 4.32; 95% CI, 1.70–10.97; p = .001) and NG (OR, 6.08; 95% CI, 2.18–16.96; p < .001) were significantly associated with male sex, while TV was more frequently encountered among female individuals (OR, 4.34; 95% CI, 1.49–12.50; p = .003). Mycoplasma genitalium infection was detected most commonly by urine samples, while rectal swabs were the leading source of positive tests for CT. Compared with fully identified patients, those tested anonymously were 6-fold more likely to be tested positive for TV (adjusted OR, 6.49; 95% CI, 2.06–20.42; p = .001).ConclusionsChlamydia trachomatis and NG are the leading non-HIV STDs in Northern Israel. Anonymous tests predict higher positivity of TV. Rectal sampling should be increasingly used because of its efficacy in detecting CT infections.