As someone with an "Excellent" level ability to search the internet,

An outbreak is called an epidemic when there is a sudden increase in cases. As COVID-19 began spreading in Wuhan, China, it became an epidemic. Because the disease then spread across several countries and affected a large number of people, it was classified as a pandemic. From the much-battered Centers for Disease Control (CDC).

Ebola was an "Outbreak" in a few countries. Nasty as it was, it didn't spread all over the place.

• Epidemic: Sudden increase in cases of a disease.
  
  
• Epidemiology: Study of disease and other health outcomes, their causes in a population, and how they can be controlled.
  
  
• Outbreak: A higher-­than-expected number of occurrences of disease in a specific location and time.
  
  
• Pandemic: Event in which a disease spreads across several countries and affects a large number of people.