Pandemic

A pandemic (paen'dEmIk ) is an epidemic of an infectious disease that has spread across a large region, for instance multiple continents or worldwide, affecting a substantial number of individuals. Widespread endemic diseases with a stable number of infected individuals such as recurrences of seasonal influenza are generally excluded as they occur simultaneously in large regions of the globe rather than being spread worldwide. Throughout human history, there have been a number of pandemics of diseases such as smallpox. The most fatal pandemic in recorded history was the Black Death—also known as The Plague—which killed an estimated 75–200 million people in the 14th century. The term had not been used then but was used for later epidemics, including the 1918 influenza pandemic—more commonly known as the Spanish flu. The most recent pandemics include the HIV/AIDS pandemic, the 2009 H1N1 pandemic and the COVID-19 pandemic. Almost all these diseases still circulate consistently among humans though their impact now is far less. How to define the point at which a pandemic ends and endemicity begins is not fully standardized, but the candidate variables to include in such an operational definition are known. In response to the COVID-19 pandemic, recently 194 member states of the World Health Organization began negotiations on an International Treaty on Pandemic Prevention, Preparedness and Response with a requirement to submit a draft of this treaty to the 77th World Health Assembly during its 2024 convention. This is expected to set rules for dealing with a pandemic by the international community. A medical dictionary definition of pandemic is "an epidemic occurring on a scale that crosses international boundaries, usually affecting people on a worldwide scale". 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 contagious—i.e.