Furuse Yuki, Oshitani Hitoshi
Tohoku University Graduate School of Medicine, 980-8575 Sendai, Japan.
Viruses. 2017 Apr 16;9(4):82. doi: 10.3390/v9040082.
Although there have been many epidemiological reports of the inter-country transmission of measles, systematic analysis of the global transmission dynamics of the measles virus (MV) is limited. In this study, we applied phylogeographic analysis to characterize the global transmission dynamics of the MV using large-scale genetic sequence data (obtained for 7456 sequences) from 115 countries between 1954 and 2015. These analyses reveal the spatial and temporal characteristics of global transmission of the virus, especially in Australia, China, India, Japan, the UK, and the USA in the period since 1990. The transmission is frequently observed, not only within the same region but also among distant and frequently visited areas. Frequencies of export from measles-endemic countries, such as China, India, and Japan are high but decreasing, while the frequencies from countries where measles is no longer endemic, such as Australia, the UK, and the USA, are low but slightly increasing. The world is heading toward measles eradication, but the disease is still transmitted regionally and globally. Our analysis reveals that countries wherein measles is endemic and those having eliminated the disease (apart from occasional outbreaks) both remain a source of global transmission in this measles elimination era. It is therefore crucial to maintain vigilance in efforts to monitor and eradicate measles globally.
尽管已有许多关于麻疹跨国传播的流行病学报告，但对麻疹病毒（MV）全球传播动态的系统分析仍然有限。在本研究中，我们应用系统发育地理学分析，利用1954年至2015年间来自115个国家的大规模基因序列数据（共获得7456个序列）来描述MV的全球传播动态。这些分析揭示了该病毒全球传播的时空特征，特别是自1990年以来在澳大利亚、中国、印度、日本、英国和美国的传播情况。不仅在同一地区，而且在遥远且人员往来频繁的地区之间，都经常观察到病毒传播。来自中国、印度和日本等麻疹流行国家的输出频率较高但呈下降趋势，而来自澳大利亚、英国和美国等已不再流行麻疹的国家的频率较低但略有上升。世界正朝着消除麻疹的目标迈进，但该疾病仍在区域和全球范围内传播。我们的分析表明，在这个麻疹消除时代，麻疹流行国家和已消除该疾病（除偶尔爆发外）的国家仍然都是全球传播的源头。因此，在全球监测和消除麻疹的努力中保持警惕至关重要。
