Survey of evolutionary rate estimates in Ebola virus

Ebola virus first appeared in 1976 in Sudan and Zaire as an illness characterized by fever, severe diarrhea, vomiting and a high fatality rate. Since then there were multiple Ebola outbreaks, some deadlier than others. The ongoing epidemic begun in 2013 in Guinea, and then spread to neighboring countries, leading to over 4900 estimated deaths in the region by late 2014, and continuing to ravage the region. The disease is highly contagious when there is a skin-to-skin contact, with the burial practices exasperating the problem of transmission.

Recent spread of epidemic outside of remote villages underscores the critical need to develop vaccination and/or treatment options to be broadly available in potentially affected areas. However, up to date vaccine development has been challenging , in part because previous outbreaks were relatively small, thus, little was understood about the evolution of the Ebola virus. Currently, more genomes of Ebola are sequenced and available, thus, enabling phylogenetic and molecular evolutionary studies. In order to know whether vaccine or antibody treatments will maintain efficacy, the nature of genetic change in the virus (especially in the targeted regions) must be ascertained. Thus, in this project we survey published estimates of evolutionary rates of various Ebola genes and/or strains to determine (a) the most conserved genes as the most promising vaccine candidates, and (b) whether the rate of evolutionary changes in the virus has increased in recent epidemics compared to previous ones.