Coronaviruses are a group of very diverse, enveloped, single-stranded (+) RNA viruses. Coronavirus infection can affect certain types of animals, as well as humans. Over the past two decades, coronaviruses have caused epidemic outbreaks of two respiratory diseases: severe acute respiratory syndrome (SARS-CoV) and Middle East respiratory syndrome (MERSCoV). At the end of December 2019, a new variant of coronavirus capable of being transmitted from person to person was identified in Wuhan, China, which caused an outbreak of viral pneumonia. On March 11, 2020, a new variant of the SARS-CoV-2 coronavirus in terms of quantity and geographical distribution prompted the World Health Organization (WHO) to declare the COVID-19 outbreak a pandemic. This review examines the origin, clinical symptom, and prevalence rate in the world.