Before revision: After the first infected patient detected in Wuhan, China in December, 2019 with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, the COVID-19 (CO means corona, VI is virus, D is disease, 19 is the year of discovery) disease spread globally due to its high contagious nature and became an ongoing pandemic.
After revision: The lack of recommended drugs or vaccines to deal with the COVID-19 (CO means corona, VI is virus, D is disease, 19 is the year of discovery) disease spread globally due to its high contagious nature and became an ongoing pandemic.