Background The global incidence target for the elimination of hepatitis C among people who inject drugs (PWID) is <2/100. In Norway, the hepatitis C epidemic is concentrated in PWID. Immigrants are the second most important risk group for chronic infection. We modelled the incidence of hepatitis C among active PWID, and the prevalence of chronic infection among active PWID, ex-PWID and immigrants in Norway until 2022. Methods We built a stochastic compartmental model, which was informed using data from national data sources, literature, and expert opinion. We report median values with 95% credible intervals (CrI). Results The model estimated 30 (95% Crl: 13–52) new infections among active PWID in 2022, or 0.37/100 (95% Crl: 0.17–0.65), down from a peak of 726 (95% Crl: 506–1,067) in 2000. Across all groups, the model estimated 3,202 (95% Crl: 1,273–6,601) chronically infected persons in 2022. Results were robust in sensitivity analyses. Conclusions Norway provides an example of the feasibility of hepatitis C elimination in a setting with a concentrated epidemic, high coverage of harm reduction services and no treatment restrictions. Continued momentum is needed to further reduce the transmission and burden of hepatitis C in Norway.

中文翻译：

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监测挪威消除丙型肝炎这一公共卫生威胁的进展：针对注射吸毒者和移民的建模研究

背景 消除注射吸毒者(PWID)中丙型肝炎的全球发病率目标是<2/100。在挪威，丙型肝炎流行集中在吸毒者中。移民是慢性感染的第二大风险群体。我们对 2022 年之前挪威活跃注射吸毒者中丙型肝炎的发病率以及活跃注射吸毒者、前注射吸毒者和移民中慢性感染的患病率进行了建模。方法我们建立了一个随机区室模型，该模型使用来自国家数据源、文献的数据提供信息，以及专家意见。我们报告的中值具有 95% 的可信区间 (CrI)。结果 该模型估计 2022 年活跃吸毒者中有 30 例（95% Crl：13-52）新感染，即 0.37/100（95% Crl：0.17-0.65），低于峰值 726 例（95% Crl：506-1,067） ）在 2000 年。在所有组中，该模型估计 2022 年将有 3,202 名（95% Crl：1,273-6,601）名慢性感染者。敏感性分析结果稳健。结论 挪威提供了在流行集中、减害服务覆盖率高且无治疗限制的环境下消除丙型肝炎的可行性的例子。挪威需要持续的动力来进一步减少丙型肝炎的传播和负担。