When it comes to Africa, different nations can be a lot more susceptible to diseases and recurring outbreaks. Unfortunately Ethiopia falls in this category.
Aside from border regions, Ethiopia is a reasonably safe place to travel. While security situations can sometimes crumble and be a disruption to travellers, crime within Ethiopia's borders isn't too dangerous.
Africa is notoriously difficult to get around. The lack of infrastructure, public transport and good roads makes most of the continent a nightmare for travellers.