擴大 HIV “篩檢與治療” 策略對臺灣男男同性間性行為傳染愛滋疫情的防治效果：數理模式研究

Abstract

背景：男男間性行為是當前臺灣人類免疫不全病毒 (human immunodeficiency virus, HIV) 的主要傳播途徑。在目前HIV篩檢與抗病毒藥物治療 (antiretroviral therapy, ART) 涵蓋率下，每年約有2000位新診斷男男間性行為相關HIV個案。本研究目的為以傳染病動態數理模式評估擴大實施「HIV篩檢與治療」政策對於臺灣男男間性行為者HIV疫情的影響。 方法：本研究建構一精確描述臺灣男男間性行為族群HIV疫情之傳播動態數理模式，將年齡結構、危險族群結構及人口學變遷納入考量，並以1990到2014年HIV監測數據校正模型各項參數。我們以數理模擬方式評估擴大HIV篩檢至每年一次且於診斷後立即給予ART治療，或是等到CD4小於500 cells/μL時再給予ART治療，對於男男間性行為者HIV疫情未來趨勢的影響。 結果：與維持目前篩檢及治療涵蓋率相較，若擴大HIV篩檢至每年一次，且有90%的個案診斷後皆於CD4小於500 cells/μL時即接受ART治療，則在未來35年內可降低HIV新感染人數達46%。倘若擴大篩檢至每年一次，且90%的個案皆於診斷後立即給予ART治療，則在未來35年內將能降低HIV新感染人數達58%，並且在2025年時消除男男間性行為相關HIV疫情 (WHO定義HIV疫情消除為HIV發生率小於0.001/年)。 結論：本研究的結果支持在臺灣擴大HIV篩檢至每年一次以及診斷後立即給予ART治療，以達在10年後消除男男間性行為相關HIV疫情的終極防疫目標。

Background: In Taiwan, HIV epidemic is now driven by unsafe sexual behavior, especially among men who have sex with men (MSM). There are now around 2,000 new MSM-HIV cases annually, under current HIV testing and antiretroviral treatment (ART) coverage. We aimed to evaluate the impact of further expanding HIV “test-and-treat” strategy on the HIV epidemic trend among MSM in Taiwan, using a dynamic model. Methods: We constructed a dynamic model of HIV transmission, disease progression, and HIV cascade among MSM, taking age/risk structure and demographic transition into consideration. The model was fitted to HIV surveillance data from 1990 to 2014. We evaluated the impact of expanding HIV testing to once annually, followed by either starting ART immediately after HIV diagnosis or starting ART when CD4 count < 500 cells/μL. Findings: Compared with current practice, expansion of HIV “Test-and-Treat” strategy to annual testing followed by starting ART when CD4 count < 500 cells/μL in 90% cases will cut new HIV infections by 46% in the next 35 years. Annual HIV testing followed by immediate ART after HIV diagnosis in 90% cases will cut new HIV infections by 58% by 2050, and practically eliminate HIV epidemic (defined as an HIV incidence lower than 0.001/year by World Health Organization) by 2025. Interpretation: Our results support the expansion of HIV “Test-and-Treat” strategy in Taiwan to annual testing followed by immediate ART, with the aim to eliminate HIV epidemic among MSM in the next 10 years.