Evaluation of an HIV saliva test for the detection of HIV-1 and HIV-2 antibodies in high-risk populations in Abidjan, Côte d'Ivoire.

To evaluate saliva testing in a West African field situation where both HIV-1 and HIV-2 are present, a cross-sectional study was conducted among female sex workers (FSWs) and their stable male partners (SMPs) at a STD/HIV clinic in Abidjan, Côte d'Ivoire. Saliva samples were collected with the Omni-SAL device and tested for antibodies to HIV-1 or HIV-2 by GACELISA. The HIV seroprevalence was 71% among 468 FSWs and 61% among 31 SMPs. Salivary HIV antibodies were detected in all 227 HIV-1-seropositive, in all 6 HIV-2-seropositive and in 115 of 117 dually seroreactive participants, while no salivary HIV antibodies were detected in 148 of 149 seronegative participants. The sensitivity and specificity of the saliva test were 99.4% and 99.3% respectively, and the positive and negative predictive values were 99.7% and 98.7% respectively. In this West African field situation saliva testing has a high validity compared to serum testing. The Omni-SAL and GACELISA combination is an alternative strategy to serological testing because of its high sensitivity and specificity, the ease and safety of sample collection and its relatively low cost.

Evaluation of simple diagnostic algorithms for Neisseria gonorrhoeae and Chlamydia trachomatis cervical infections in female sex workers in Abidjan, Côte d'Ivoire.

OBJECTIVE: To generate simple algorithms for the diagnosis of cervical infection with Neisseria gonorrhoeae or Chlamydia trachomatis in female sex workers in Abidjan, Côte d'Ivoire and to evaluate their validity. METHODS: From October 1992 to the end of June 1993, female sex workers were interviewed and clinically examined at a confidential clinic. N gonorrhoeae was cultured on modified Thayer-Martin medium and C trachomatis was detected by polymerase chain reaction. The associations of gonococcal or chlamydial cervical infection with sociodemographic, behavioural, clinical, and biological factors were assessed and three algorithms were generated. The validity parameters of these diagnostic algorithms were calculated and compared to those of standard algorithms and mass treatment. RESULTS: Among 683 women, cervical infection was present in 239 (35%). The sensitivity an algorithm incorporating sociodemographic and behavioural factors and symptoms, of an algorithm incorporating clinical signs and simple laboratory tests, and of a combined algorithm was 83%, 86%, and 79% respectively while the specificity was 32%, 44%, and 54%, and the positive predictive value 40%, 46%, and 48% respectively. A standard algorithm incorporating only the symptom vaginal discharge, and a standard algorithm requiring both the symptom vaginal discharge and the presence of an endocervical mucopurulent discharge on examination had a sensitivity of 44% and 18%, a specificity of 75% and 95%, and a positive predictive value of 49% and 67% respectively. CONCLUSIONS: The algorithms generated in this study may be useful for the control of cervical infections in female sex workers in resource poor settings in the absence of rapid, inexpensive, and accurate laboratory tests for the diagnosis of cervical infections.