Department of Tropical Medicine, Medical Microbiology and Pharmacology, Asia-Pacific Institute of Tropical Medicine and Infectious Diseases, John A. Burns School of Medicine, University of Hawaii at Manoa, Honolulu, HI 96813, USA.
Virology. 2010 Sep 30;405(2):505-12. doi: 10.1016/j.virol.2010.05.033.
Dengue is an expanding arboviral disease of variable severity characterized by the emergence of virus strains with greater fitness, epidemic potential and possibly virulence. To investigate the role of dengue virus (DENV) strain variation on epidemic activity we studied DENV-2 viruses from a series of South Pacific islands experiencing outbreaks of varying intensity and clinical severity. Initially appearing in 1971 in Tahiti and Fiji, the virus was responsible for subsequent epidemics in American Samoa, New Caledonia and Niue Island in 1972, reaching Tonga in 1973 where there was near-silent transmission for over a year. Based on whole-genome sequencing and phylogenetic analysis on 20 virus isolates, Tonga viruses were genetically unique, clustering in a single clade. Substitutions in the pre-membrane (prM) and nonstructural genes NS2A and NS4A correlated with the attenuation of the Tongan viruses and suggest that genetic change may play a significant role in dengue epidemic severity.
登革热是一种不断扩大的虫媒病毒性疾病，其严重程度存在差异，其特点是出现了适应能力更强、具有更大流行潜力且可能具有更高毒力的病毒株。为了研究登革病毒（DENV）株变异对流行活动的作用，我们研究了一系列经历不同强度和临床严重程度爆发的南太平洋岛屿上的 DENV-2 病毒。该病毒最初于 1971 年在塔希提岛和斐济出现，随后于 1972 年在美属萨摩亚、新喀里多尼亚和纽埃岛引发了后续的疫情，并于 1973 年传播到汤加，在那里该病毒几乎沉默传播了一年多。通过对 20 个病毒分离株进行全基因组测序和系统进化分析，汤加病毒在基因上是独特的，聚集在一个单一的分支中。包膜（prM）和非结构基因 NS2A 和 NS4A 中的替换与汤加病毒的衰减相关，这表明遗传变化可能在登革热流行严重程度中发挥重要作用。
