What is a flu pandemic? Is it different from an epidemic?

A disease epidemic occurs when there are more cases of that disease than normal. A pandemic is a worldwide epidemic of a disease.

 

An influenza pandemic may occur when a new flu virus appears for which the human population has no immunity. With the increase in global transport, as well as urbanization and overcrowded conditions in some areas, epidemics due to a new flu viruses are likely to take hold around the world, and become a pandemic faster than before.

 

The World Health Organization (WHO) has defined the phases of a pandemic to provide a global framework to aid countries in pandemic preparedness and response planning. Pandemics can be either mild or severe in the illness and death they cause, and the severity of a pandemic can change over the course of that pandemic.