Ebola fever and Viral haemorrhagic fever

Ebola fever noun - A severe and often fatal disease in humans and nonhuman primates (monkeys and chimpanzees) caused by the Ebola virus; characterized by high fever and severe internal bleeding; can be spread from person to person; is largely limited to Africa.

Viral haemorrhagic fever and Ebola fever are semantically related. In some cases you can use "Viral haemorrhagic fever" instead a noun phrase "Ebola fever".

Viral haemorrhagic fever noun - A group of illnesses caused by a viral infection (usually restricted to a specific geographic area); fever and gastrointestinal symptoms are followed by capillary hemorrhage.

Ebola fever and viral haemorrhagic fever are semantically related. Sometimes you can replace phrase "Ebola fever" with "Viral haemorrhagic fever", this phrases are similar.