Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2016 Oct 21:6:35822.
doi: 10.1038/srep35822.

The 2014 Ebola virus outbreak in West Africa highlights no evidence of rapid evolution or adaptation to humans

Xingguang Li  1   2 , Junjie Zai  3 , Haizhou Liu  4 , Yi Feng  1   2 , Fan Li  1   2 , Jing Wei  1   2 , Sen Zou  1   2 , Zhiming Yuan  3 , Yiming Shao  1   2
Affiliations

The 2014 Ebola virus outbreak in West Africa highlights no evidence of rapid evolution or adaptation to humans

Xingguang Li et al. Sci Rep. .

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.

PubMed Disclaimer

Figures

Figure 1
Figure 1. Root-to-tip regression of a maximum likelihood (ML) phylogenetic tree of GP gene sequences of EBOV.
The residual of each GP gene sequence of EBOV is highlighted using different colors and circles.
Figure 2
Figure 2. Estimation of past population dynamics of EBOV isolated from West Africa using the Bayesian coalescent-based non-parametric skygrid model.
Left-hand axis represents effective number of infections (Ne) multiplied by mean viral generation time (τ). Black line and shaded blue region represent the median and 95% high posterior density (HPD) intervals of EBOV past population dynamics, respectively.
Figure 3
Figure 3. Bayesian maximum clade credibility (MCC) phylogenetic tree of GP gene sequences of EBOV isolated from West Africa.
Branch lengths are scaled in time by enforcing a strict molecular clock. Posterior probability for major nodes is shown.
See this image and copyright information in PMC

References

    1. Feldmann H. & Geisbert T. W. Ebola haemorrhagic fever. Lancet 377, 849–862, doi: 10.1016/S0140-6736(10)60667-8 (2011). - DOI - PMC - PubMed
    1. Ebola W. H. O. Situation Report - 30 March 2016. Available at http://apps.who.int/ebola/current-situation/ebola-situation-report-30-ma... (2016).
    1. Baize S. et al. Emergence of Zaire Ebola virus disease in Guinea. The New England journal of medicine 371, 1418–1425, doi: 10.1056/NEJMoa1404505 (2014). - DOI - PubMed
    1. Gire S. K. et al. Genomic surveillance elucidates Ebola virus origin and transmission during the 2014 outbreak. Science 345, 1369–1372, doi: 10.1126/science.1259657 (2014). - DOI - PMC - PubMed
    1. WHO. Ebola virus disease outbreak. Available at http://www.who.int/csr/disease/ebola/en/ (2016).

Publication types