Cátedra de Virología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.
PLoS One. 2010 Jan 18;5(1):e8751. doi: 10.1371/journal.pone.0008751.
Previous studies in Argentina have documented a general prevalence of Hepatitis C Virus (HCV) infection close to 2%. In addition, a high prevalence of HCV has been recently reported in different Argentinean small rural communities. In this work, we performed a study aimed at analyzing the origins and diversification patterns of an HCV outbreak in Wheelwright, a small rural town located in Santa Fe province (Argentina).A total of 89 out of 1814 blood samples collected from people living in Wheelwright, were positive for HCV infection. The highest prevalence (4.9%) was observed in people older than 50 years, with the highest level for the group aged between 70-79 years (22%). The RFLP analyses showed that 91% of the positive samples belonged to the HCV-1b genotype. The E1/E2 and NS5B genes were sequenced, and their phylogenetic analysis showed that the HCV-1b sequences from Wheelwright were monophyletic. Bayesian coalescent-based methods were used to estimate substitution rates and time of the most recent common ancestor (tMRCA). The mean estimated substitution rates and the tMRCA for E1/E2 with and without HVR1 and NS5B were 7.41E-03 s/s/y and 61 years, 5.05E-03 s/s/y and 58 years and 3.24E-03 s/s/y and 53 years, respectively. In summary, the tMRCA values, the demographic model with constant population size, and the fact that the highest prevalence of infection was observed in elder people support the hypothesis that the HCV-1b introduction in Wheelwright initially occurred at least five decades ago and that the early epidemic was characterized by a fast rate of virus transmission. The epidemic seems to have been controlled later on down to the standard transmission rates observed elsewhere.
先前在阿根廷的研究记录了丙型肝炎病毒（HCV）感染的普遍流行率接近 2%。此外，最近在阿根廷不同的小型农村社区也报告了 HCV 的高流行率。在这项工作中，我们进行了一项研究，旨在分析 Wheelwright 爆发的 HCV 起源和多样化模式，Wheelwright 是位于圣达菲省（阿根廷）的一个小型农村城镇。从居住在 Wheelwright 的 1814 个人的血液样本中，共检测到 89 份 HCV 感染阳性。最高的流行率（4.9%）出现在 50 岁以上的人群中，其中 70-79 岁年龄段的人群最高（22%）。RFLP 分析显示，91%的阳性样本属于 HCV-1b 基因型。对 E1/E2 和 NS5B 基因进行了测序，其系统发育分析表明，Wheelwright 的 HCV-1b 序列是单系的。贝叶斯合并法被用来估计替代率和最近共同祖先（tMRCA）的时间。不包括 HVR1 和 NS5B 的 E1/E2 和 NS5B 的平均估计替代率和 tMRCA 分别为 7.41E-03 s/s/y 和 61 年，5.05E-03 s/s/y 和 58 年和 3.24E-03 s/s/y 和 53 年。总之，tMRCA 值、人口大小不变的人口模型以及感染的最高流行率出现在老年人中，这支持了 HCV-1b 最初在 Wheelwright 引入的时间至少在五十年前的假设，并且早期的流行具有快速传播的特点。后来，该流行似乎得到了控制，达到了其他地方观察到的标准传播率。
