The Effectiveness of Antiretroviral Therapy in Mitigating New HIV Infections in Southwest China: An Ecological Study.

Background: Antiretroviral therapy (ART) has been shown to reduce the number of local HIV (Human Immunodeficiency Virus) reported cases; however, there is insufficient research on the relationship between new HIV infections and ART. This study utilized real-world data to evaluate the community-level effectiveness of ART in reducing new HIV infections.

Methods: Ecological study was designed to establish the relationship between ART quality and new HIV infections. New HIV infections were identified through an expanded testing system in 2018-2023; ART quality was evaluated based on ART-treated clients in 2016-2023, and non-probabilistic sampling was performed. Generalized linear models was employed to assess associations between metrics of ART effectiveness and new HIV infections. Statistical significance was set at α = 0.05 with 95% confidence intervals.

Results: A total of 3836 new HIV infections were identified, yielding an overall incidence of 2.1%. Treatment coverage for the entire population was 80.8%, and the proportion of clients with an increased CD4 count was 61.0% of the entire population. In the generalized linear modeling, four key factors were associated with reduced new HIV infections: a greater number of clients undergoing treatment, a higher proportion of clients demonstrated CD4 count improvement, higher level of CD4 in baseline, and a reduction in reported cases (β = -0.04, -0.03, -0.01, 0.17 respectively).

Conclusion: This ecological study verified that expanding treatment coverage, optimizing the effectiveness of antiretroviral treatment and elevating baseline CD4 counts could curb community-level new HIV infections. Early detection, prompt treatment, and effective ART are crucial for curbing HIV transmission in regions mainly driven by sexual transmission and with high cumulative incidence rates.