The WHO (World Health Organization) Level 6 requirement for a pandemic requires serious outbreaks in communities in two or more different WHO regions.
According to the WHO, a pandemic can start when three conditions have been met:
- Emergence of a disease new to a population.
- Agents infecting humans, causing serious illness.
- Agents spreading easily and sustainably among humans.
A disease or condition is not a pandemic merely because it is widespread or kills many people; it must also be infectious. For instance, cancer is responsible for many deaths but is not considered a pandemic, because the disease is not infectious or contagious.