llama-South America, Asia, North Africa, and Europe had the others: goats, sheep, pigs, cows, horses, donkeys, camels, water buffalo, reindeer, yaks, nithans, and cattle. Smallpox is a viral infection that usually enters the body through the nose or throat. From here the virus travels to the lungs, where it multiplies and spreads to the lymphatic system. Within a few days, large blisters begin to appear all over the victim's skin. Starting with the hands and the face, and then spreading to cover the rest of the body, each blister is packed full of smallpox DNA. If punctured, these blisters become highly infectious, projecting fresh smallpox particles into the air and onto surrounding
surfaces - like someone else's skin! The total incubation period lasts around 12 days, by which point the patient will either die or survive - but throughout that period, he may have passed the disease to an enormous number of people. The disease requires close human contact to replicate and survive. For thousands of years, the people of Eurasia lived in close proximity to the largest
variety of domesticated mammals in the world - eating, drinking, and breathing in the germs these animals bore. Over time, animal infections crossed species, evolving into new strains which became deadly to man. Diseases like smallpox, infuenza and measles were in fact the deadly inheritance of the Eurasian farming tradition - the product of thousands of years spent farming cattle, pigs, horses, goats and sheep. These epidemic Eurasian diseases f ourished in dense communities and tend to explode in sudden, overwhelming epidemics of infection and death. Transmitted via coughing, sneezing and touching, they wreaked devastation throughout Eurasian history - and in the era before antibiotics, thousands would die. With each epidemic eruption, some people would always survive, acquiring antibodies and immunities which they could pass on to the next generation. Over time, the population of Europe gained increasing levels of such immunity, and the devastating
impact of traditional infections decreased.