Ebola Conquers West Africa — More to Come?

Abstract

In 1976, the world's attention was caught by two almost simultaneous outbreaks of a new and then a mysterious virus named Ebola (Fig. 1) in the Sudan and what was then Zaire, now known as the Democratic Republic of Congo. Since then, sporadic outbreaks caused by Ebola virus have resulted in approximately 2387 cases and 1590 deaths (http://www.who.int/mediacentre/factsheets/fs103/en/). This year, Ebola virus returned to the center stage as the Western African countries of Guinea, Liberia, and Sierra Leone are facing an unprecedented and uncontrolled outbreak caused by a new Zaire ebolavirus strain that has been linked by epidemiological evidence to a potential “patient zero” who succumbed to infection in December, 2013 (Baize et al., 2014). The number of cases in this outbreak has surpassed that for all previously reported Ebola virus outbreaks combined. As of September 18, 2014, there have been more than 5347 cases with 2630 deaths; these numbers include 318 infected healthcare workers, half of whom have died (http://www.cdc.gov/vhf/ebola/outbreaks/guinea/index.html). In past outbreaks, the case fatality rates have varied from 25% to 90% (http://www.who.int/mediacentre/factsheets/fs103/en/); the case fatality rate of the current outbreak is 53% (http://www.cdc.gov/vhf/ebola/outbreaks/guinea/index.html.). However, due to limited access to Ebola treatment units and the stigma associated with this disease, many infections may have gone unreported, so the true number of infected people is most likely much higher, and the true case fatality rate will not be known until the outbreak is over.