Epidemics are rapid increases in the incidence of disease. When an epidemic affects a large number of people across multiple countries or continents it is then known as a pandemic. In the 19th and early 20th century, there was great progress in the fight against infectious diseases. However, since the second half of the 20th century an emergence of new infectious diseases has been observed, such as HIV/AIDS, severe acute respiratory syndrome (SARS), H1N1 influenza, Ebola, and Zika. In 2012, infectious diseases still accounted for almost one third of global deaths (32%). Every year, more than 14 million people die because of infectious diseases disrupting the economic, political, and societal environment in areas affected.
By 2030, extant diseases will be compounded by new infections and diseases