Wasley A, Alter M J
Hepatitis Branch, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA.
Semin Liver Dis. 2000;20(1):1-16. doi: 10.1055/s-2000-9506.
Hepatitis C Virus (HCV) infection appears to be endemic in most parts of the world, with an estimated overall prevalence of 3%. However, there is considerable geographic and temporal variation in the incidence and prevalence of HCV infection. Using age-specific prevalence data, at least three distinct transmission patterns can be identified. In countries with the first pattern (e.g., United States, Australia), most infections are found among persons 30-49 years old, indicating that the risk for HCV infection was greatest in the relatively recent past (10-30 years ago) and primarily affected young adults. In countries with the second pattern (e.g., Japan, Italy), most infections are found among older persons, consistent with the risk for HCV infection having been greatest in the distant past. In countries with the third pattern (e.g., Egypt), high rates of infection are observed in all age groups, indicating an ongoing high risk for acquiring HCV infection. In countries with the first pattern, injection drug use has been the predominant risk factor for HCV infection, whereas in those with the second or third patterns, unsafe injections and contaminated equipment used in healthcare-related procedures appear to have played a predominant role in transmission. Much of the variability between regions can be explained by the frequency and extent to which different risk factors have contributed to the transmission of HCV. Because different strategies are required to interrupt different patterns of HCV transmission, determining the epidemiology of HCV infection in areas where that information has not yet been assessed is critical for developing appropriate prevention programs.
丙型肝炎病毒（HCV）感染似乎在世界大部分地区呈地方性流行，估计总体患病率为3%。然而，HCV感染的发病率和患病率在地理和时间上存在相当大的差异。利用特定年龄的患病率数据，至少可以确定三种不同的传播模式。在具有第一种模式的国家（如美国、澳大利亚），大多数感染发生在30至49岁的人群中，这表明HCV感染风险在相对较近的过去（10至30年前）最高，主要影响年轻人。在具有第二种模式的国家（如日本、意大利），大多数感染发生在老年人中，这与HCV感染风险在遥远的过去最高相一致。在具有第三种模式的国家（如埃及），所有年龄组的感染率都很高，这表明感染HCV的风险持续很高。在具有第一种模式的国家，注射吸毒一直是HCV感染的主要危险因素，而在具有第二种或第三种模式的国家，医疗相关程序中使用的不安全注射和受污染设备似乎在传播中起了主要作用。不同地区之间的许多差异可以通过不同危险因素对HCV传播的贡献频率和程度来解释。由于中断不同的HCV传播模式需要不同的策略，因此在尚未评估该信息的地区确定HCV感染的流行病学对于制定适当的预防计划至关重要。
