Editorial on the Research Topic Emerging and old viral diseases: Antiviral drug discovery from medicinal plants manageIt has been mentioned in a number of studies that viruses and viral diseases may have had a profound effect on human evolution, culture, and civilization. The type of viruses affecting human beings have changed with time, depending on human density and climatic conditions (de S Leal and Zanotto, 2000;Sharp and Simmond, 2011). The human genome is considered by scientists to be not only a hereditary blue-print, but also as a niche colonized by numbers of endogenous retrovirus-derived retroposons and other mobile genetic elements (de Koning et al., 2011). When and how this started remains an unanswered question, as to other questions like whether such viral interference of human genomes or viral diseases affecting humans came in distinct waves or were simply a part of gradual infiltration amidst continual interactions between viruses and humans.Irrespective of the past, recent decades have witnessed emergence of dozens of new viruses and re-emergence of old viruses, a number of them being zoonotic. Zoonotic viral diseases are transmitted from a host animal harboring the virus to humans, occasionally through a secondary host. The rise in incidences of new zoonotic viral diseases can be attributed to a number of factors including live animal markets, wildlife hunting and consumption, intensive farming of domestic animals and wildlife, and last but not the least-increases in human habitat and agricultural land, leading to massive deforestation of forests with concomitant increases in human-wildlife contacts (Wolfe et al., 2005;Magouras et al., 2020). It has also been suggested that global climate changes (due to human-caused exorbitant atmospheric increases in carbon dioxide and greenhouse gases like methane) are also causative factors behind the incidences of emerging infectious diseases (