Changing epidemiology of SARS-CoV in the context of COVID-19 pandemic

SARS-CoV-2 is a new form of β-coronavirus that has been recently discovered and is responsible for COVID 19 pandemic. The earliest infection can be traced back to Wuhan, China. From there it has spread all over the world. Keeping in view the above perspective, an attempt is made in order to find out the epidemiological pattern of COVID 19 pandemic, if any, in different geo-climatological regions of the world in terms of case incidence and mortality. This study is also an endeavor to review and analyze the gradual changes of the genetic makeup of SARS-CoV from evolutionary and epidemiological perspectives. The raw data of COVID-19 cases and death incidences were collected from the World Health Organization (WHO) website from the time period: 1(st) April to 6(th) April, 2020. The data that are utilized here for general and Case fatality rate (CFR) based analysis. Western pacific region, European region and Americas have the greatest number of infected cases (P < 0.001); whereas deaths have been found to be significantly higher in Europe (P < 0.001). Total number of confirmed cases and deaths in south-east Asia are comparatively lower (P < 0.001). Case fatality rate (CFR) has also found significant for European region. SARS-CoV-2 is considered to be a strain of SARS-CoV that has a high rate of pathogenicity and transmissibility. Result indicated that the European region has been affected mostly for both cases and death incidences. The novel mutations in SARS-CoV-2 possibly increase the virus infectivity. Genetic heterogeneity of this virus within the human population might originate as the representatives of naturally selected virus quasispecies. In this context, the presence of the asymptomatic individuals could be a significant concern for SARS-CoV-2 epidemiology. Further studies are required to understand its genetic evolution and epidemiological significance.