Infectious Disease Epidemiology Group, Weill Cornell Medicine-Qatar, Cornell University, Qatar Foundation-Education City, Doha, Qatar; World Health Organization Collaborating Centre for Disease Epidemiology Analytics on HIV/AIDS, Sexually Transmitted Infections, and Viral Hepatitis, Weill Cornell Medicine-Qatar, Cornell University, Qatar Foundation-Education City, Doha, Qatar; Department of Population Health Sciences, Weill Cornell Medicine, Cornell University, New York, NY, USA; Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK.
Mathematics Program, Department of Mathematics, Statistics, and Physics, College of Arts and Sciences, Qatar University, Doha, Qatar.
Lancet HIV. 2022 Jul;9(7):e496-e505. doi: 10.1016/S2352-3018(22)00100-X.
The incidence of HIV infection among female sex workers and their clients in the Middle East and north Africa is not well known. We aimed to assess HIV incidence, the contribution of heterosexual sex work networks to these numbers, and the effect of interventions by use of mathematical modelling.
In this modelling study, we developed a novel, individual-based model to simulate HIV epidemic dynamics in heterosexual sex work networks. We applied this model to 12 countries in the Middle East and north Africa that had sufficient data to estimate incidence in 2020 and the impact of interventions by 2030 (Algeria, Bahrain, Djibouti, Iran, Libya, Morocco, Pakistan, Somalia, South Sudan, Sudan, Tunisia, and Yemen). Model-input parameters were provided through a systematic review of HIV prevalence, sexual and injecting behaviours, and risk group size estimates of female sex workers and clients. Model output was number of incident HIV infections under different modelling scenarios for each country. Summary statistics were generated on these model output scenarios.
Based on the output of our model, we estimated a total of 14 604 (95% uncertainty interval [UI] CI 7929-31 819) new HIV infections in the 12 countries in 2020 among female sex workers, clients, and spouses, which constituted 28·1% of 51 995 total new cases in all adults in these 12 countries combined. Model-estimated number of new infections in 2020 in the 12 countries combined was 3471 (95% UI 1295-10 308) in female sex workers, 6416 (3144-14 223) in clients, and 4717 (3490-7288) in client spouses. Contribution of incidence in heterosexual sex work networks to total incidence varied widely, ranging from 3·3% in Pakistan to 71·8% in South Sudan and 72·7% in Djibouti. Incidence in heterosexual sex work networks was distributed roughly equally among female sex workers, clients, and client spouses. Estimated incidence rates among female sex workers per 1000 person-years ranged from 0·4 (95% UI 0·0-7·1) in Yemen to 34·3 (17·2-59·6) in South Sudan. In countries where HIV acquisition through injecting drug use creates substantial exposure for female sex workers who inject drugs, estimated incidence rates per 1000 person-years ranged from 5·1 (95% UI 0·0-35·1) in Iran to 45·8 (0·0-428·6) in Pakistan. The model output predicted that any of the programmed interventions would substantially reduce incidence. Even when a subpopulation did not benefit directly from an intervention, it benefited indirectly through reduction in onward transmission, and indirect impact was often half as large as the direct impact.
Substantial HIV incidence occurs in heterosexual sex work networks across the Middle East and north Africa with client spouses being heavily affected, in addition to female sex workers and clients. Rapid scaling-up of comprehensive treatment and prevention services for female sex workers is urgently needed.
Qatar National Research Fund (a member of Qatar Foundation), the Biostatistics, Epidemiology, and Biomathematics Research Core at the Weill Cornell Medicine-Qatar, Qatar University-Marubeni, the UK Medical Research Council, and the UK Department for International Development.
在中东和北非，女性性工作者及其客户中的艾滋病毒感染发病率尚不清楚。我们旨在评估艾滋病毒发病率、异性性工作网络对这些数字的贡献，以及通过使用数学模型进行干预的效果。
在这项建模研究中，我们开发了一种新的、基于个体的模型，用于模拟异性性工作网络中的艾滋病毒流行动态。我们将该模型应用于 12 个拥有足够数据来估计 2020 年发病率和 2030 年干预效果的中东和北非国家（阿尔及利亚、巴林、吉布提、伊朗、利比亚、摩洛哥、巴基斯坦、索马里、南苏丹、苏丹、突尼斯和也门）。模型输入参数通过对女性性工作者和客户的艾滋病毒流行率、性和注射行为以及风险群体规模的系统评估提供。模型输出是在不同建模情景下，每个国家的新发艾滋病毒感染人数。对这些模型输出情景进行了总结统计。
根据我们模型的输出结果，我们估计在 2020 年，12 个国家中，女性性工作者、客户及其配偶的艾滋病毒新发感染总数为 14604 例（95%置信区间[CI] 7929-31819），占这 12 个国家所有成年人中总共 51995 例新发感染病例的 28.1%。我们模型估计，在这 12 个国家中，2020 年新发感染病例数在女性性工作者中为 3471 例（95% CI 1295-10308），在客户中为 6416 例（3144-14223），在客户配偶中为 4717 例（3490-7288）。异性性工作网络中发病率对总发病率的贡献差异很大，从巴基斯坦的 3.3%到南苏丹的 71.8%和吉布提的 72.7%不等。异性性工作网络中的发病率在女性性工作者、客户和客户配偶之间大致平均分布。每 1000 人年的女性性工作者估计发病率范围从也门的 0.4（95% CI 0.0-7.1）到南苏丹的 34.3（17.2-59.6）。在因注射吸毒而对女性性工作者造成大量暴露的国家，每 1000 人年的估计发病率范围从伊朗的 5.1（95% CI 0.0-35.1）到巴基斯坦的 45.8（0.0-428.6）。模型输出预测，任何有计划的干预措施都将大大降低发病率。即使某个亚人群不能直接从干预中受益，它也会通过减少传播而间接受益，间接影响通常是直接影响的一半。
在中东和北非，异性性工作网络中存在大量艾滋病毒发病率，除了女性性工作者和客户外，客户配偶也受到严重影响。迫切需要迅速扩大对女性性工作者的全面治疗和预防服务。
卡塔尔国家研究基金会（卡塔尔基金会的一个成员）、威尔康奈尔医学院-卡塔尔的生物统计学、流行病学和生物数学研究核心、卡塔尔大学-丸红、英国医学研究理事会和英国国际发展部。
