Establishing HIV-1 recent infection surveillance using a rapid recency test among newly diagnosed HIV Cases in Bangkok

Abstract

Introduction: Surveillance of new HIV infections is essential for epidemic control. However, traditional systems rely on complex laboratory procedures that require transporting blood samples to central laboratories, resulting in delays of several weeks. These delays limit timely data use and reduce the effectiveness of public health responses. The Rapid Test for Recent HIV Infection (RTRI) provides a fast, accurate alternative that can be conducted at healthcare facilities. This study aimed to develop an improved HIV surveillance system that addresses these limitations and to analyze factors associated with recent infections to support public health strategy development.
Methods: A real-time HIV surveillance system was developed using RTRI, implemented across participating healthcare facilities. An automated data linkage platform was built to integrate the Hospital Information System (HIS) with the Bangkok Smart Monitoring System (BSMS), enabling continuous tracking and analysis. A total of 1,041 individuals were tested, and recent infections were identified using two criteria: Viral Load (VL) >1,000 copies/mL and CD4 >200 cells/ L. The study further examined associations with demographics, gender, age, and behavioral risks.

Results: The study found that the prevalence of new HIV infections was 7.68% based on the Viral Load >1,000 copies/mL criterion and 5.38% based on the CD4 >200 cells/ L criterion. Individuals with high Viral Load were 52.52 times more likely to be newly infected (p < 0.001), while those with high CD4 levels were 1.87 times more likely to be newly infected (p = 0.008). Analysis by gender and age group showed that males, particularly young adults aged 20-24 years, had the highest infection rate at 12.5%, with a high prevalence also observed in the 25-29 age group (8.0%). Among females, the highest prevalence was found in older adults, with the 40-44 age group showing a peak prevalence of 15.8% and the 45-49 age group at 11.5%. A significant difference was observed between the Viral Load and CD4 criteria (p = 0.033), with Viral Load being a more accurate indicator as it directly reflects the presence of the virus, whereas CD4 levels may be influenced by other factors.

Conclusion and Recommendations: The findings highlight that the developed surveillance system significantly improves the efficiency of tracking and detecting new HIV infections through real-time data integration, enabling precise situation assessments and strategic planning. This system enhances the ability to monitor and control the spread of HIV more effectively. While Viral Load is a more precise criterion, CD4 can serve as an alternative in resource-limited settings. The data obtained from this study provide valuable insights for public health strategy development, contributing to long-term epidemic control.