Pandemic

A pandemic is an epidemic that spreads across multiple countries or continents and affects an unusually large number of people.

Epidemic: A disease outbreak in a population that exceeds what is normally expected. A pandemic is an epidemic whose spread extends across countries or continents.
Plague of Justinian: A major wave of plague that affected the Byzantine Empire and surrounding regions beginning in 541 CE. It is an early documented pandemic spanning regions linked by empire and trade.
Disease surveillance: The ongoing collection and analysis of health data to detect and monitor disease. Surveillance helps identify emerging outbreaks and track their spread.
Excess mortality: The number of deaths above the level expected under normal conditions during a given period. It captures pandemic deaths missed by counts limited to confirmed infections.
Endemic: A disease or infectious agent that is consistently present in a particular population or region. Endemic describes sustained presence, not unusually broad geographic spread.
Basic reproduction number: The average number of secondary infections caused by one infected person in a fully susceptible population. It helps describe how readily an emerging infection can spread.
Black Death: The fourteenth-century pandemic of plague that killed millions across Europe, Asia, and North Africa. It shows how a pandemic can transform societies as well as population size.
Contact tracing: The process of identifying and notifying people exposed to an infectious case. It can interrupt transmission chains when cases are found promptly.
Healthcare capacity: The ability of a health system to provide care with its available staff, facilities, and supplies. A surge of cases can overwhelm capacity and worsen outcomes.
Outbreak: A sudden increase in disease cases in a specific place or population. An outbreak may remain local rather than becoming a pandemic.

Linked from 9 pages