Somehow the most severe outbreak of Ebola fever ever, yet restricted to Westafrica, had to step back in the news. Well, what is Ebola fever anyway? To put it bluntly: You die in 40-90% of all cases [1] and if you do, you do it in severe pain within 6-16 days after showing the first symptoms [2]. Ah, and there is neither a real cure, nor a vaccine, of course [2].
An infection with the Ebola virus begins with harmless-seeming flu-like symptoms like fever, headache and nausea, but eventually causes severe internal bleeding. Cloggs of blood finally result in death by multiple organ failure [2]. Treatment is limited to rehydration and pain management, rendering it palliative [1]. Although the first reported outbreak dates back to 1972 [3], it is still not clear how the virus is actually transmitted to humans. Fruit bats are suspected to be the natural reservoir of the virus, and if not contact to them, eating of ‘bush kills’ (meat of wild animals) is connected to Ebola outbreaks [1]. Once the virus is transmitted to humans it spreads by direct contact with infected patients or deceased [2].
The major problem in developing treatments and even vaccines for Ebola is, however, actually something good: Rarity of the disease prevents effective human trials. In consequence the ‘Food and Drug Administration’ (FDA), responsible for the admission of drugs in the USA, would allow animal testing as sole proof of drug efficacy [1]. But still the vaccine should function in at least two animal models, including non-human primates, which is a rarely met criterion [2] . Any actual treatment of an Ebola outbreak would have to combine several strategies to be fast and potent enough: Viral replication, blood coagulation and immune response are possible targets [2]. Improvement of infrastructure, be it transport or healthcare related, and better education of the
public concerning nature and the transmission mechanism of Ebola are clearly as essential for stopping the disease, as is actual medical care.
Let’s hope for the best!
Felix Spenkuch
Further reading:
[1] N. J. Sullivan, J. E. Martin, B. S. Graham, G. J. Nabel, Nature Review Microbiology 2009, 7, 393-400.
[2] H. Feldmann, T. W. Lancet 2011, 377, 849-862.
[3] D. L. Heymann, Dr. J. S. Weisfeld, P. A. Webb, K. M. Johnson, T. Cairns, H. Berquist, J Infect Dis. 1980, 142, 3, 372-376.