Global Spread of Viruses

The spreading of viruses and viral infectious diseases across the globe is referred as epidemiology. The epidemiologic studies of infectious diseases have concentrated on the factors which influence acquisition and spread, because this knowledge is essential for developing methods of prevention and control. Basically, epidemiologic studies and the application knowledge which gained from them have been essential to the control of the epidemic diseases, such as cholera, plague, smallpox, yellow fever, and typhus.