Diagnosis of HIV infection using mass community rapid testing in Santiago, Chile

Abstract

Background: Chile has had the highest increase in new HIV infections in Latin America in the last ten years. Therefore, Chile should follow the WHO recommends on the use of rapid testing in the community to reduce the enormous barriers to diagnosis that exist until today. The objective of this study was to evaluate the performance of rapid tests prior diagnosis of HIV infection in the general population using mass testing in the community. Study design: Six HIV rapid tests were evaluated using positive and negative plasma panels. Moreover, the Ag/Ab assays were revaluated using whole blood obtained from HIV-positive and seronegative individuals. After evaluation, we selected an Ag/Ab test to determine the prevalence of HIV infection in the study participants. A total of 3,102 people were included. Results: In the evaluation with plasma and whole blood the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) was 100% for the tests. In the 3102 study participants, we found a total of 41 reactive individuals. After adjustments, a total of 32 people who participated in the study were diagnosed with HIV infection. These results indicate that the Ag/ab assay had a high sensitivity, specificity, NPV, and PPV. Conclusions: We validated available rapid tests and demonstrated the feasibility of mass testing in the community. Confidentiality was guaranteed with a link to healthcare. After adjustments, we found an HIV infection prevalence of 1.03%. This is twice the estimate of official sources. Therefore, rapid tests have adequate sensitivity and specificity for use in HIV diagnostics.

Keywords

• HIV
• Rapid test
• Visual test
• Ag/Ab assay