ABSTRACT
Ebola virus disease (EVD) is a highly contagious hemorrhagic viral infection that affects human and non-human primates. It presents as a non-specific febrile illness that mimics other tropical diseases such as malaria and typhoid fever, and an early diagnosis can be missed. Five species have so far been isolated. Although the virus clearly has a zoonotic origin, its natural reservoir remains unknown. Human-to-human transmission follows an index case that is usually impossible to recognize, which is the very reason it kills many health workers in the early days of the epidemic. The case fatality is estimated to range between 25% and 90%, with an average of 50%. Measures to prevent transmission are easier to implement in rural areas, since the population density is low and communities are more homogeneous with nearly the same ethnic identity and cultural practices. In cities, the dynamics are usually diverse, with mixed ethnicities, and overcrowded informal settlements perpetually encumbered with inadequate access to safe water and sanitation facilities. Urban populations are highly mobile and have a greater risk of human–human contacts, especially in public transport vehicles, shopping malls, restaurants, churches and recreational facilities. These dense human environments can act as serious incubators of disease and hence become hazardous to all travelers.
