An emerging disease is a disease of which the true incidence increases in a significant way in a given population, of a given area and during a given period, in comparison with the current epidemiological situation of this disease. This definition can be used as well for human diseases than for plant or animal ones.

Climate and Environmental factors are major contributors to many emerging and re-emerging infectious diseases. Environmental changes including pollution may lead to re-emerging diseases and/or pandemics such as COVID-19. To that effect several papers can be seen at the site Geospatial Health.