The AIDS Epidemic Model 2023 for Estimating HIV Trends and Transmission Dynamics in Asian Epidemic Settings.

Background: Thirteen Asian countries use the AIDS Epidemic Model (AEM) as their HIV model of choice. This article describes AEM, its inputs, and its application to national modeling.

Setting: AEM is an incidence tool used by Spectrum for the Joint United Nations Programme on HIV/AIDS global estimates process.

Measuring HIV Acquisitions Among Partners of Key Populations: Estimates From HIV Transmission Dynamic Models.

Background: Key populations (KPs), including female sex workers (FSWs), gay men and other men who have sex with men (MSM), people who inject drugs (PWID), and transgender women (TGW) experience disproportionate risks of HIV acquisition. The UNAIDS Global AIDS 2022 Update reported that one-quarter of all new HIV infections occurred among their non-KP sexual partners. However, this fraction relied on heuristics regarding the ratio of new infections that KPs transmitted to their non-KP partners to the new infections acquired among KPs (herein referred to as "infection ratios").

Evolving HIV epidemics: the urgent need to refocus on populations with risk.

Purpose Of Review: To explore the comparative importance of HIV infections among key populations and their intimate partners as HIV epidemics evolve, and to review implications for guiding responses.

Recent Findings: Even as concentrated epidemics evolve, new infections among current and former key population members and their intimate partners dominate new infections. Prevalent infections in the general population grow primarily because of key population turnover and infections among their intimate partners.

Updates to the Spectrum/Estimations and Projections Package model for estimating trends and current values for key HIV indicators.

Background: The Spectrum model is used by national programs and UNAIDS to prepare annual estimates of the status of the HIV epidemic in 160 countries. The model and assumptions are updated regularly under the guidance of the UNAIDS Reference Group on Estimates, Modelling and Projections in response to new data, studies, and program needs. This study describes the most recent updates for the 2016 round of estimates.

The impact of Thailand's public health response to the HIV epidemic 1984-2015: understanding the ingredients of success.

Introduction: Thailand has been heralded as a global leader in HIV prevention and treatment, and its experience with the HIV/AIDS epidemic holds valuable lessons for public health. This paper documents Thailand's response to its HIV epidemic from the late 1980s until today, and analyses its epidemiological impact (incidence and mortality). We discuss the association between the trajectory of HIV incidence and mortality rates over time, and the programmatic investments, policies and interventions that were implemented in the last three decades.

Is a HIV vaccine a viable option and at what price? An economic evaluation of adding HIV vaccination into existing prevention programs in Thailand.

Background: This study aims to determine the maximum price at which HIV vaccination is cost-effective in the Thai healthcare setting. It also aims to identify the relative importance of vaccine characteristics and risk behavior changes among vaccine recipients to determine how they affect this cost-effectiveness.

Methods: A semi-Markov model was developed to estimate the costs and health outcomes of HIV prevention programs combined with HIV vaccination in comparison to the existing HIV prevention programs without vaccination.

HIV transmission rates in Thailand: evidence of HIV prevention and transmission decline.

Background: Analysis of HIV transmission rates has provided insight into the impacts of HIV-related prevention programming and policies in the United States by providing timely information beyond incidence or prevalence alone. The purpose of this analysis is to use transmission rates to assess past prevention efforts and explore trends of the epidemic in subpopulations within Thailand.

Methods: Asian Epidemic Model HIV incidence and prevalence were used to calculate transmission rates over time nationally and among high-risk populations.

The economics of effective AIDS treatment in Thailand.

Introduction: The speed with which Thailand has scaled up public provision of antiretroviral therapy (ART) has been unprecedented, with more than 80 000 individuals on treatment at the end of 2006 through Thailand's National Access to Antiretroviral Program for People Living with HIV/AIDS (NAPHA). This paper projects the cost effectiveness, the affordability and the future fiscal burden of NAPHA to the government of Thailand under several different policy scenarios until the year 2025.

Methods: An economic/epidemiological model of access to ART was constructed, and this composite model was calibrated to economic and epidemiological data from Thailand and other countries.