title: The 2014 Ebola virus outbreak in West Africa highlights no evidence of rapid evolution or adaptation to humans.
abstract: Following its immergence in December 2013, the recent Zaire Ebola virus (EBOV) outbreak in West Africa has spread and persisted for more than two years, making it the largest EBOV epidemic in both scale and geographical region to date. In this study, a total of 726 glycoprotein (GP) gene sequences of the EBOV full-length genome obtained from West Africa from the 2014 outbreak, combined with 30 from earlier outbreaks between 1976 and 2008 were used to investigate the genetic divergence, evolutionary history, population dynamics, and selection pressure of EBOV among distinct epidemic waves. Results from our dataset showed that no non-synonymous substitutions occurred on the GP gene coding sequences of EBOV that were likely to have affected protein structure or function in any way. Furthermore, the significantly different dN/dS ratios observed between the 2014 West African outbreak and earlier outbreaks were more likely due to the confounding presence of segregating polymorphisms. Our results highlight no robust evidence that the 2014 EBOV outbreak is fast-evolving and adapting to humans. Therefore, the unprecedented nature of the 2014 EBOV outbreak might be more likely related to non-virological elements, such as environmental and sociological factors.
authors: State Key Laboratory for Infectious Disease Prevention and Control, National Center for AIDS/STD Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.|Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, Zhejiang, China.
authors: Xingguang
authors: X
authors: Li
authors: Key Laboratory of Agricultural and Environmental Microbiology, Wuhan Institute of Virology, University of Chinese Academy of Sciences, Wuhan, Hubei, China.
authors: Junjie
authors: J
authors: Zai
authors: Centre for Emerging Infectious Diseases, State Key Laboratory of Virology, Wuhan Institute of Virology, University of Chinese Academy of Sciences, Wuhan, Hubei, China.
authors: Haizhou
authors: H
authors: Liu
authors: State Key Laboratory for Infectious Disease Prevention and Control, National Center for AIDS/STD Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.|Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, Zhejiang, China.
authors: Yi
authors: Y
authors: Feng
authors: State Key Laboratory for Infectious Disease Prevention and Control, National Center for AIDS/STD Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.|Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, Zhejiang, China.
authors: Fan
authors: F
authors: Li
authors: State Key Laboratory for Infectious Disease Prevention and Control, National Center for AIDS/STD Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.|Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, Zhejiang, China.
authors: Jing
authors: J
authors: Wei
authors: State Key Laboratory for Infectious Disease Prevention and Control, National Center for AIDS/STD Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.|Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, Zhejiang, China.
authors: Sen
authors: S
authors: Zou
authors: Key Laboratory of Agricultural and Environmental Microbiology, Wuhan Institute of Virology, University of Chinese Academy of Sciences, Wuhan, Hubei, China.
authors: Zhiming
authors: Z
authors: Yuan
authors: State Key Laboratory for Infectious Disease Prevention and Control, National Center for AIDS/STD Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.|Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou, Zhejiang, China.
authors: Yiming
authors: Y
authors: Shao
mesh_terms: D000354:Africa, Western / Q000453:epidemiology; D001499:Bayes Theorem; D004196:Disease Outbreaks; D029043:Ebolavirus / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D019143:Evolution, Molecular; D019142:Hemorrhagic Fever, Ebola / Q000453:epidemiology / Q000821:virology*; D006801:Humans; D016013:Likelihood Functions; D010802:Phylogeny; D017423:Sequence Analysis, RNA; D000073336:Whole Genome Sequencing