The Ebola fever is caused by the Ebola virus, leading to a hemorrhagic fever which is fatal in 25–90 % of cases . This disease has been known since 1976, with the first outbreak being described at the river Ebola (Democratic Republic of Congo). Since then, about 35 outbreaks have been registered, with the highest number of cases of one single outbreak so far being 425 (Uganda 2001). Therefore, the epidemic in Western Africa in 2014/15 represents a hitherto completely unknown dimension of Ebola disease .
In principle, the transmission of this highly infectious virus is possible via any kind of body fluid. The smallest number of viruses suffices to trigger the disease. Ritual ablutions of the dead, which are common in large parts of Africa, pose a special danger . Until 2014, the outbreaks described were locally restricted and primarily situated in rural areas. They came to a halt after a comparatively short period, being practically self-limiting. Some local societies established traditional rites of quarantine that could be enforced with the rigor of a tribal culture and therefore prevented a further spread of the disease .
In the past, repeated outbreaks of Ebola happened. This is primarily due to the fruit bat, persisting in tropical rain forests, being a natural reservoir of the Ebola virus. The eradication of Ebola is thus impossible in the foreseeable future .
The Ebola epidemic in 2014/15 stands out significantly from previous epidemics with regard to intensity and dynamics. This is primarily due to the fact that this epidemic expanded to the urban population as well as across borders. On one hand this results in the number of possibly infected people being significantly higher. On the other hand the weakness or absence of social structures in urban settings lowers the social and medical control in case of illness. The previously mentioned funeral rites as well as the completely overburdened and already weak health care systems favored the rapid and massive spread of the disease. The fear of contagion led many health workers to leave health service provision which led to an acute shortage of staff in hospitals and health centers. After a short period, local health care systems literally collapsed. Other sectors were severely affected as well. This also resulted in massive declines in the gross national product of the respective countries (estimates differ between US $6.2 and 25 billion), in food shortages and the (almost) complete exodus of foreign professionals, also coming from neighboring countries, holding key positions in the economy .
Aid for the overburdened countries started pretty delayed in mid-2014, leading to a so far virtually unknown volume of investment in a very short amount of time. In August 2014, the WHO had provided an estimated budget of $ 500 million: in September Ban Ki-Moon called for one billion. To date, the United Nations Mission for Ebola Emergency Response (UNMEER) specified a sum required for emergency aid of $ 1.5 billion. Indeed, in contrast to other catastrophes, the majority of funds necessary have already been paid.
These amounts are a multiple of national health budgets (Guinea: US $ 98 million p.a.; Sierra Leone: US $ 81 million p.a.; Liberia: US $ 112 million p.a.)  and health-related development aid, respectively, the affected countries have received in recent years. Whereas financial aid for health care has continuously been reduced or diverted during the past two decades, large amounts of money were suddenly made available. Thereby, Ebola caught up with a group of ‘exceptional diseases’ which are of international interest, while other equally relevant diseases and health systems needs are often ignored by politics. Over the past decade most funds were allocated to vertical programs to combat three diseases only (malaria, AIDS and TB), while the most significant ‘killers’ (e.g. diarrhea) are almost completely ignored . Disease-specific programs in particular led to a collapse of community-based education programs, since these only engaged in, for example, bed nets and condoms instead of general health promotion.
This trend was exacerbated by the reduction of professional expertise in the so-called implementing organizations of development cooperation. While medical professionals with specific expertise on the health care systems of countries poor in resources used to be a fixed factor in development assistance, today this expertise is usually purchased externally on short notice. With regard to the health care sector, a stable and consistent development and human resource policy on this basis is only possible to a limited extent.