Contextual risk factors for hepatitis C among young persons who inject drugs

7.项目总结 背景：在年轻人中存在一种新的丙型肝炎病毒(丙型肝炎病毒)感染流行 从郊区和农村地区注射毒品(PWID)。丙型肝炎病毒主要通过相关的风险行为传播 注射吸毒(IDU)。2016年，美国国家科学院(NAS)研究了 在美国消除丙型肝炎病毒，定义为停止病毒在美国的传播。在其第一阶段报告中， NAS确定年轻的PWID是感染丙型肝炎病毒风险最高的人，也是丙型肝炎病毒的主要驱动力 在以前丙型肝炎病毒感染率较低或适中的美国非城市社区，今天的发病率。至 到目前为止，还没有已知的研究完全阐明为什么丙型肝炎病毒在新一代PWID患者中的发病率增加 (Ng-PWID)，主要由来自郊区和农村社区的非西班牙裔白人组成。 我们最近的研究表明，过去十年可能发生的变化是背景和结构上的 增加郊区NG-PWID感染丙型肝炎病毒风险的因素。目标：我们提出一种 NG-PWID及其个人(以自我为中心)注射、性和支持网络的纵向研究。 我们将在36个月内每6个月收集一次数据，以评估随着时间的推移对丙型肝炎风险的影响(I)社会 网络因素，(2)自然和社会地理因素，(3)注射吸毒的社会规范，和(4)感知注射吸毒和 丙型肝炎病毒污名。方法：我们将招募420名PWID(年龄18-30岁)和大约1156名他们的注射网络 会员(18岁及以上)来自芝加哥、伊利诺伊州及周边郊区。招聘将在以下时间进行 大型注射器服务方案(SSP)的两个社区实地站点，并通过在大型、开放的直接外联 毒品市场领域。将收集两个参与者及其注射、性和性行为的六种类型的数据 支助网络成员：(1)参与者的社会人口特征、吸毒模式和做法， 和性行为；(Ii)网络规模、特征和网络成员之间的关系特征 (3)通过检测获得的艾滋病毒和丙型肝炎病毒感染状况；(4)地点的地理数据；以及 参与者及其网络成员居住、购买毒品、注射和 会见性和注射伴侣，(V)评估参与者网络和 具体的行为环境，以及(Vi)对感知的注射吸毒者和丙型肝炎病毒污名的评估。公共卫生 意义：拟议的研究将(I)提高我们对背景因素和结构因素的理解 推动NG-PWID中丙型肝炎的发病率；(Ii)为NG-PWID创新策略的发展提供信息 (例如，网络干预，扩大直接抗病毒治疗)，以实现消除丙型肝炎病毒的目标 以及(Iii)提供开发更现实的计算模型所需的关键数据 解决了影响丙型肝炎病毒发病率的个人、社会和结构层面因素的复杂相互作用 以确定实现丙型肝炎病毒消除最有效的干预策略组合(S)。

7. PROJECT SUMMARY Background: An emerging epidemic of hepatitis C virus (HCV) infection exists among young persons who inject drugs (PWID) from suburban and rural areas. HCV is primarily transmitted via risk practices associated with injection drug use (IDU). In 2016, the National Academy of Sciences (NAS) examined the feasibility of HCV elimination in the U.S., defined as cessation of viral transmission in this country. In its phase-1 report, NAS determined that young PWID are the people at greatest risk for HCV and are the primary drivers of HCV incidence today in non-urban U.S. communities that previously had low to modest rates of HCV infection. To date, no known study has fully elucidated why HCV incidence is increasing in this “new generation” of PWID (NG-PWID), which is composed predominantly of non-Hispanic Whites from suburban and rural communities. Our recent study suggests that what may have changed over the past decade are contextual and structural factors that heighten suburban NG-PWID's risk of becoming HCV-infected. Objective: We propose a longitudinal study among NG-PWID and their personal (egocentric) injection, sexual, and support networks. We will collect data every 6 months for 36 months to assess over time the impact on HCV risk of (i) social network factors, (ii) physical and social geographic factors, (iii) social norms of IDU, and (iv) perceived IDU and HCV stigma. Methods: We will recruit 420 PWID (ages 18-30) and about 1,156 of their injection network members (age 18 and over) from Chicago, Illinois, and surrounding suburban areas. Recruitment will occur at two community field sites of a large syringe services program (SSP) and through direct outreach in large, open drug market areas. Six types of data will be collected on both participants and their injection, sexual, and support network members: (i) participant socio-demographic characteristics, drug use patterns and practices, and sexual practices, (ii) network size, characteristics, and features of relationships among network members (e.g., strength of tie), (iii) HIV and HCV infection status through testing, (iv) geographic data on the location and characteristics of places where participants and their network members reside, purchase drugs, inject, and meet sex and injection partners, (v) an assessment of social norms within both the participant's network and specific behavioral settings, and (vi) an assessment of perceived IDU and HCV stigma. Public Health Significance: The proposed research will (i) improve our understanding of the contextual and structural factors driving HCV incidence among NG-PWID, (ii) inform the development of innovative strategies for NG-PWID (e.g., network interventions, direct antiviral HCV treatment scale up) toward the goal of HCV elimination in the U.S. set forth by DHHS, and (iii) provide crucial data needed to develop more realistic computational models that address the complex interplay of individual, social, and structural level factors affecting HCV incidence in order to identify the most effective combination(s) of intervention strategies for achieving HCV elimination.