concepts
key cases and current trends
Infectious diseases have decimated empires, determined the outcome of wars, and shaped the fate of humanity since ancient times, and they remain, to this day, a major medical and socioeconomic challenge, responsible for over 25% of the annual mortality worldwide. More than 2,000 years ago, around 430 BCE, typhoid fever killed one third of the Athenian troops during the Peloponnesian War and is thought to have contributed to the fall of Athens; the plague of Justinian in the 6th century CE claimed 10,000 deaths daily and up to one quarter of the known human population; the Black Death caused 50 million deaths during the 14th century; and the 1918 to 1919 Spanish flu pandemic had 50 to 100 million victims worldwide.Approximately 1,400 human pathogens are currently known, and investigators predict that approximately 10 to 40 new virus species will appear by 2020. [Source: Encyclopedia of Science and Technology Communication; Pandemics, Origins of]
origins of pandemics