Epidemiological studies of COVID-19 disease: A story of SARS CoV-2 infection from origin to hospital

The Chinese population having epidemiological link with wholesale market of seafood develop respiratory illness with pneumonia like clinical presentations in Hubei Province, Wuhan City, recently in December 2019. Laboratory results revealed a novel coronavirus that was named severe acute respiratory syndrome coronavirus-2 (SARS CoV-2) and disease it caused given name of coronavirus disease 2019 (COVID-19). COVID-19 turn out to be third outbreak of human pathogenic coronaviruses and first pandemic of 21st century. The previous coronaviruses proved merely as a tip of iceberg after emergence of recently identified SARS-CoV-2 with potential of pandemic status that significantly revealed the concealed capabilities of virulence and contagiousness of betacoronaviruses group. The aim of this review is to discuss the origin of COVID-19, transmission patterns, susceptible hosts, factors that increase disease severity, nucleic acid base diagnosis, mortality and morbidity rates and therapeutic option against COVID-19. The diagnostic methods like microarray and RNA-targeting CRISPR were adopted recently for COVID-19 diagnosis after advancing them further for rapid and accurate detection of COVID-19 and high throughput