COVID-19: A MULTI-HOST PANDEMIC

SARS-CoV-2, the causal agent of the COVID-19 pandemic, is related to a group of viruses (Sarbecovirus) that circulate in horseshoe bats. Its origin is still uncertain, as there is lack of an identifiable intermediate host species for the proximal animal ancestor of SARS-CoV-2. Irrespective of its origin, SARS-CoV-2 has been shown to replicate in many mammalian species. So far, over forty species have been found to be susceptible to SARS-CoV-2 infection, and natural infections have been documented in at least 23 species of distant mammalian orders, including Primata, Rodentia, Carnivora, and Arthiodactyla. In two of those species, minks and white tailed deer, continued transmission among conspecifics occurred following introduction of SARS-CoV-2 from humans, at a rate which makes mink farms and deer populations suitable compartments where the virus may be maintained and evolve, and then perhaps spill back to humans or other animals as a new variant, as suggested by molecular evidence. Considering the above, what is truly unique about this pandemic, and adds a major obstacle to attain its control, is its multi-host nature. This is another compelling example of the relevance of the 'One Health' approach. This approach recognizes the inextricable links between people and nature, and visualizes the health and disease phenomenon from an integrative perspective. The COVID-19 pandemic urges us to acknowledge the interconnection between people and the remaining forms of life, and with the environments they share, and demonstrates that the improvement of global health needs a collaborative, multisectoral, and transdisciplinary approach, acting at the local, regional and global levels. This concept becomes paramount when taking into account that most diseases affecting humans in the last decades -not only COVID-19 - have been caused by pathogens originated in animals.