Animal Virus Ecology and Evolution Are Shaped by the Virus Host-Body Infiltration and Colonization Pattern

Evolution, Ecology, and Zoonotic Transmission of Betacoronaviruses: A Review

Coronavirus infections have been a part of the animal kingdom for millennia. The difference emerging in the twenty-first century is that a greater number of novel coronaviruses are being discovered primarily due to more advanced technology and that a greater number can be transmitted to humans, either directly or via an intermediate host. This has a range of effects from annual infections that are mild to full-blown pandemics. This review compares the zoonotic potential and relationship between MERS, SARS-CoV, and SARS-CoV-2. The role of bats as possible host species and possible intermediate hosts including pangolins, civets, mink, birds, and other mammals are discussed with reference to mutations of the viral genome affecting zoonosis. Ecological, social, cultural, and environmental factors that may play a role in zoonotic transmission are considered with reference to SARS-CoV, MERS, and SARS-CoV-2 and possible future zoonotic events.

Decoding the global outbreak of COVID-19: the nature is behind the scene

The sudden emergence of SARS-CoV-2 causing the global pandemic is a major public health concern. Though the virus is considered as a novel entity, it is not a completely new member. It is just a new version of previously emerged human SARS corona virus. The rapid evolving nature by changing host body environment and extreme environmental stability, collectively makes SARS-CoV-2 into an extremely virulent genetic variant. The evolution of the virus has been occurred by the continuous process of molecular genetic manipulation, through mutation, deletion and genetic recombinationevents. Different host body environment acts as the supportive system for the pathogen which creates extreme selective pressure. By the process of genetic evolution the pathogen developes new characters. Then the new version of the virus has been naturally selected by susceptible human host and adapt itself inside the host body causing deadly effect. Moreover, extreme environmental stability helps in the process of viral survival outside the host and its transmission. Thus both the host body or internal environment and the external environment performs equally as a source, responsible for shaping the genetic evolution of the SARS-CoV-2 towards theCOVID-19 disease fitness in nature in a pandemic form.