SCREENING FOR SEXUALLY-TRANSMITTED DISEASES IN RURAL SOUTH-AFRICAN WOMEN

Objective: This paper reports on a study undertaken in a rural area of South Africa, to develop a non-laboratory tool to screen for sexually transmitted diseases (STDs) among family planning clients. Methods: A cross sectional study was performed of 249 consecutive women attendin g a family planning service between November and December 1994. A ques tionnaire was administered, and a clinical examination and laboratory tests conducted. Sociodemographic, clinical, and other non-laboratory variables that were significantly associated with laboratory evidence of infection were combined to produce non-hierarchical scoring systems for three ''syndromes'': gonococcal and/or chlamydial cervical infect ion, trichomoniasis, and cervical infection and/or trichomoniasis comb ined. The sensitivity, specificity, and predictive values of the scori ng systems as a screening tool were assessed against the gold standard of laboratory tests. Results: The prevalence of reproductive tract in fections among the study participants was as follows: Chlamydia tracho matis 12%, Neisseria gonorrhoeae 3%, Trichomonas vaginalis 18%, and ba cterial vaginosis 29%. Although vaginal discharge and other symptoms w ere frequently reported, symptoms bore no relation to the presence of infection. The following independent associations with gonococcal/chla mydial cervical infection were found: age less than 25 years and cervi cal mucopus and/or friability. Abnormal discharge on examination, visi ble inflammatory changes of the cervix (increased redness), no recent travel, and unemployment were associated with trichomoniasis. The comb ination of trichomonas and/or cervical infection (''STD syndrome'') wa s associated with cervical mucopus/friability, unemployment, lack of f inancial support, and increased redness of the cervix. Of the three sc oring systems developed on the basis of these associations, that of th e ''STD syndrome'' achieved the best performance characteristics as a screening tool, with a sensitivity of 62%, specificity of 74%, and pos itive predictive value of 48%. Conclusion: STDs are common in a popula tion of rural, sexually active women attending a family planning servi ce. In resource poor settings, non-laboratory screening tools could pl ay some role in identifying and treating infections in these women, es pecially since the majority would not otherwise have been reached. How ever, such screening tools cannot be viewed as the only way to identif y STDs and should be considered as part of an overall strategy of STD control that includes, for example, good management of symptomatic ind ividuals and their partners.