Raboud J M, Boily M C, Rajeswaran J, O'Shaughnessy M V, Schechter M T
Division of Infectious Disease, University Health Network, University of Toronto, Ontario, Canada.
J Urban Health. 2003 Jun;80(2):302-20. doi: 10.1093/jurban/jtg033.
To determine the impact of the implementation of a needle-exchange program (NEP) on the spread of human immunodeficiency virus (HIV) in an injection drug user (IDU) community. We conducted a Monte Carlo simulation study of a theoretical population of 10000 IDUs. The population was followed monthly from 1984 to 2000. HIV was assumed to be transmitted only by needle sharing. The NEP was introduced in 1989 and evaluated over a period of 11 years. The impacts of the proportion of the population attending the NEP, the risk level of IDUs attending the NEP, the reduction in needle-sharing frequency, and the number of new needle-sharing partners acquired at the NEP on prevalence and incidence of HIV were determined. Increasing the proportion of the population who always attend the NEP and eliminating needle-sharing incidents among IDUs who always attended the NEP were the most effective ways of reducing the spread of HIV. Attracting high-risk users instead of lower risk users to the NEP also reduced the spread of HIV, but to a lesser extent. NEPs are effective at reducing the spread of HIV; even under the worst case scenario of low risk users more likely to attend the NEP, one additional partner per month as a result of attending the NEP, and poor NEP attendance, the estimated prevalence was still less than that from the scenario without an NEP. Under our model, NEPs were shown to reduce the spread of HIV significantly. Efforts should be focused on getting as many IDUs as possible to become regular NEP attenders and stop sharing needles rather than partially reducing the frequency of sharing by a larger number of IDUs.
为确定实施针头交换项目（NEP）对注射吸毒者（IDU）群体中人类免疫缺陷病毒（HIV）传播的影响。我们对一个由10000名注射吸毒者组成的理论人群进行了蒙特卡洛模拟研究。从1984年至2000年每月跟踪该人群。假设HIV仅通过共用针头传播。1989年引入针头交换项目并在11年期间进行评估。确定了参与针头交换项目的人群比例、参与该项目的注射吸毒者的风险水平、共用针头频率的降低以及在针头交换项目中获得的新共用针头伙伴数量对HIV流行率和发病率的影响。增加始终参与针头交换项目的人群比例以及消除始终参与该项目的注射吸毒者之间的共用针头事件是减少HIV传播的最有效方法。吸引高风险使用者而非低风险使用者参与针头交换项目也能减少HIV传播，但程度较小。针头交换项目在减少HIV传播方面是有效的；即使在低风险使用者更有可能参与该项目、因参与该项目每月多一个伙伴以及项目参与率低的最坏情况下，估计的流行率仍低于没有针头交换项目的情况。在我们的模型中，针头交换项目被证明能显著减少HIV的传播。应将努力重点放在让尽可能多的注射吸毒者成为针头交换项目的定期参与者并停止共用针头，而不是让大量注射吸毒者部分降低共用频率。
