ABSTRACT

Breaking out contagious diseases is of many threats to human-beings, and coronavirus disease-2019 (COVID-19) is an example. Because of its initial cases happened in a market specialized for sea food stuff that eat living creatures, it was verified as an infectious zoonotic disease. The first case was infected with SARS-CoV-2 was an old and infirm person suffering from symptoms on 1st December 2019. Neither of his family associates got infected, and his virus origin still unidentified. The persistence of Covid-19 pandemic may be another evidence of diseases coming out of the human-animal overlapping and disseminating through globe. Some reports proposed that bat birds and pangolins were the source of infection since coronavirus-development of such two animals undertook analogous genomic sequence for Covid-19. When Covid19 happens, many aspects shall be noticed and grasped like origin, innate hosts and intermediary hosts. Dipping down the vulnerability of disseminating from natural host to human-beings may be thoroughly requiring understanding of the natural environment of the pathogen. Identifying SARS-CoV-2 origins and intermediate hosts help understanding the outbreak dynamics, with a probability of reverse zoonosis .Whereas, failing to recognize and uncover the origins and intermediate hosts in the disease cycle can create forthcoming diseases.

KeyWords :Covid-19,virus,infection.