A pandemic is when a diseases growth is exponential and the number of cases increases each day across the world. A pandemic situation is declared when a new disease affects several countries and populations. Viral respiratory diseases are most likely to turn into a pandemic like the COVID-19. In the past, there have been numerous cases of influenza pandemics. Global pandemic is called by the World Health Organisation (WHO) after taking advice from international health experts. The WHO defines pandemics epidemics, and endemic diseases based on the rate of the spread of the disease.
An epidemic is a sudden unexpected increase in the number of cases of an illness in a specific geographical area. However, it does not mean the disease is contagious yellow fever, smallpox, measles, and polio are prime examples of epidemics. It can also refer to a disease or other specific health-related behaviour (such as smoking) if the number of cases is clearly above the expected occurrence in a community or region.
Meanwhile, a disease outbreak is endemic when it is present but limited to a partiodar region making the disease spread and rates predictable. It is also called a baseline. For example malaria is considered endemic in certain countries and regions.
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