<P> The history of smallpox extends into pre-history ; the disease likely emerged in human populations about 10,000 BC . The earliest credible evidence of smallpox is found in the Egyptian mummies of people who died some 3000 years ago . Smallpox has had a major impact on world history , not least because indigenous populations of regions where smallpox was non-native , such as the Americas and Australia , were rapidly decimated and weakened by smallpox ( along with other introduced diseases ) during periods of initial foreign contact , which helped pave the way for conquest and colonization . During the 18th century the disease killed an estimated 400,000 Europeans each year , including five reigning monarchs , and was responsible for a third of all blindness . Between 20 and 60 % of all those infected -- and over 80 % of infected children -- died from the disease . </P>
<P> The history of smallpox extends into pre-history ; the disease likely emerged in human populations about 10,000 BC . The earliest credible evidence of smallpox is found in the Egyptian mummies of people who died some 3000 years ago . Smallpox has had a major impact on world history , not least because indigenous populations of regions where smallpox was non-native , such as the Americas and Australia , were rapidly decimated and weakened by smallpox ( along with other introduced diseases ) during periods of initial foreign contact , which helped pave the way for conquest and colonization . During the 18th century the disease killed an estimated 400,000 Europeans each year , including five reigning monarchs , and was responsible for a third of all blindness . Between 20 and 60 % of all those infected -- and over 80 % of infected children -- died from the disease . </P>
when did smallpox transfer from cattle to humans
when did smallpox transfer from cattle to humans
likely emerged in human populations about 10,000 BC
likely emerged in human populations about 10,000 BC