Pandemic Threats    / 001

I. The Plague    / 002

II. Cholera     / 005

III. Smallpox    / 008

IV. Influenza    / 011

V. COVID-19     / 019

VI. Other infectious diseases that may cause pandemics    / 019

References    / 022

How Pandemics Arise    / 027

I. Characteristics of pandemics and determination criteria    / 027

II. Characteristics of pandemic-inducing infectious diseases    / 029 III. Factors contributing to pandemics of infectious diseases    / 034

References    / 047

The Challenges of Pandemics    / 053

I. Absence of a unified global community of interest    / 054

II. Monitoring systems insufficient for early warning and response    / 055