The Role of Dead Space Syringes in HIV Epidemics Amount IDU's - Drug Abuse Aspect

描述(申请人提供)：艾滋病毒继续在世界许多国家的注射吸毒者(IDU)中传播。近年来，东欧、俄罗斯联邦、印度、中国和亚洲其他地区的城市注射吸毒者中艾滋病毒感染率迅速上升，而其他城市的注射吸毒者中艾滋病毒感染率保持低和稳定，尽管注射风险很高。艾滋病毒在注射吸毒者中流行已经25年了，研究人员仍然不知道为什么这种病毒在一些地方传播得比其他地方更多。共用注射器和无保护性行为的简单比率并不能说明艾滋病毒传播的不同程度。造成艾滋病毒传播差异的一个被广泛忽视的因素是注射吸毒者使用的注射器的类型。拟议的研究是评估注射器类型在注射吸毒者艾滋病毒流行中的作用的过程中的一个步骤。到目前为止，我们已经证实，这种类型的注射器可能在艾滋病毒传播中发挥作用的生物学上是可信的，因为我们证明了高死腔注射器(HDSS)在使用和冲洗后保留的血液是低死腔注射器(LDSS)保留的血液的1000多倍。我们已经将共享HDSS的历史与流行的艾滋病毒和丙型肝炎病毒感染联系在一起，我们已经建立了数学模型，表明如果使用HDSS的注射吸毒者不到10%，与注射相关的艾滋病毒流行可能不会在城市发生。下一步是收集经验数据来检验这一发现。需要进行大型多点纵向艾滋病毒感染研究，收集有关注射吸毒者使用的注射器类型的数据，以确定注射吸毒者中HDSS与艾滋病毒感染之间的因果关系。然而，这些研究需要在时间和金钱上投入大量资金。因此，我们建议进行一项小型探索性研究，以确定欧洲、俄罗斯和亚洲注射吸毒者中艾滋病毒流行率较高的城市和注射吸毒者中艾滋病毒流行率较低的城市。我们将寻求获得有关注射吸毒者在这些城市使用的注射器类型的信息。拟议的研究有可能以最少的投资产生极其有价值的数据。拟议研究的具体目的是：比较注射吸毒者中艾滋病毒感染率高(30%)或上升(3年为5%)的城市中注射吸毒者使用的注射器类型与艾滋病毒感染率低且稳定的城市(5年为5%)相匹配的对照组中注射吸毒者使用的注射器类型。如果我们发现HDSS的使用和HIV流行率之间存在生态关联，我们将提议进行更大规模的研究，目的是更好地描述因果推断，包括性传播的作用。 公共卫生相关性：该项目获得的信息可能大大增加我们对注射吸毒者(IDU)中艾滋病毒传播的了解。如果我们发现注射吸毒者使用的注射器的类型影响艾滋病毒的传播，这可能会导致相对简单的干预措施，从而大大减少这一高危群体中的艾滋病毒传播。这反过来又可以减少艾滋病毒从注射吸毒者向普通人群的性传播。

DESCRIPTION (provided by applicant): HIV continues to spread among injecting drug users (IDUs) in many countries around the world. In recent years, cities in Eastern Europe, the Russian Federation, India, China, and other parts of Asia have experienced rapid increases in HIV prevalence among IDUs, while HIV prevalence has remained low and stable among IDUs in other cities despite high levels of injecting risk. Twenty-five years into the HIV epidemic among IDUs, researchers still do not really know why the virus spreads more in some places than others. Simple rates of syringe sharing and unprotected sex do not account for varying degrees of HIV transmission. One widely overlooked factor that could significantly contribute to these differences in HIV spread is the type of syringes that IDUs are using. The proposed study represents one step in the process of assessing the role of syringe type in HIV epidemics among IDUs. To date, we have established that it is biologically plausible that the type of syringe may play a role in HIV transmission by demonstrating that high dead-space syringes (HDSSs) retain over 1,000 times more blood after use and rinsing than low dead-space syringes (LDSSs) retain. We have linked a history of sharing HDSSs with prevalent HIV and HCV infection, and we have developed mathematical models that suggest injection-related HIV epidemics may not occur in cities, if fewer than 10% of IDUs are using HDSSs. The next step is to collect empirical data to test this finding. Large multisite longitudinal HIV incidence studies that collect data from individual IDUs on the types of syringes that they are using will be needed to establish a causal relationship between HDSSs and HIV infection among IDUs. However, these studies would require a considerable investment in time and money. Thus, we propose to conduct a small exploratory study to identify cities in Europe, Russia, and Asia where HIV prevalence among IDUs is high and cities where HIV prevalence among IDUs is low. We will seek to obtain information on the types of syringes that IDUs are using in these cities. The proposed study has the potential for yielding extremely valuable data for minimal investment. The specific aim of the proposed study is: To compare the types of syringes used by IDUs in cities where HIV prevalence among IDUs is high (>30%) or increasing (>5% per year for >3 years) with the types of syringes that IDUs are using in a matched comparison group of cities with low and stable HIV prevalence (<5% for >5 years). Should we find an ecological association between use of HDSSs and HIV prevalence, we will propose larger studies with the purpose of better delineating causal inference, including the role for sexual transmission. PUBLIC HEALTH RELEVANCE: The information obtained in this project may substantially increase our knowledge of HIV transmission among injecting drug users (IDUs). If we find that the types of syringes used by IDUs influence HIV transmission, this could lead to relatively straightforward interventions that could substantially reduce HIV transmission in this high risk group. This in turn could reduce sexual transmission of HIV from IDUs to the general population.