The spread of infectious diseases in the population is defined on the basis of many variables, including the area of ​​contagion.

An epidemic (from the Greek “epi” = sul, “demos” = people; “which is above the people”) means a disease that spreads within a well-defined area, which generally originates from a common outbreak. It is well marked over time, so much so that its beginning and end can be identified.

By pandemic (from the Greek “pan” = all; “which is among all the people”) we mean an epidemic that has spread far beyond the area of ​​origin, coming to affect large geographical areas and involving a large part of the population of all the world.

Sometimes, an epidemic can become an endemia (from the Greek “en” = inside; “which is in the people”), that is, constantly present or very frequent in a certain area, which can have seasonal cycles.

The necessary condition for an epidemic spread is the non-immunity of the people involved towards the triggering agent.

Therefore, vaccination of non-immune (such as newborns) should be encouraged to avoid epidemics of diseases that have reached an excellent control point (such as measles).

Source: web