Impact of Emerging, Re-Emerging and Zoonotic Viral Infectious Diseases, in a Virologist's Perspective.

Emerging and re-emerging viral infections have been a major threat to public health worldwide, since their recognition in the late 20th century [1]. These infectious diseases include those caused by newly identified viruses, previously known viruses that acquired additional virulence traits, and those showing spread to unaffected regions. In the last ten years, re-emergence has been noted for Zika, Ebola, MERS, Dengue, Chikungunya and avian influenza, while SFTS (severe fever with thrombocytopenia syndrome) was recognized to be caused by a novel virus. These diseases are free to move across national borders according to rapid human mobility via global airline network. With this background, any novel infectious disease anywhere in the world may have the potential for global spread.