ABSTRACT
Wuhan, China, substantially is the epicenter of the COVID-19 pandemic in December 2019. Coronavirus, the confounder virus, a zoonotic in origin was the causative agent of the disseminated disease worldwide. Structural similarities and convergence points were demonstrated between the coronavirus, SARS, and MERS viruses. Aberrantly, a subset of patients developed a serious acute respiratory distress syndrome or diffuse alveolar injury whereas the rest of the patients encountered mild or no symptoms. The pathological clinical laboratory findings are not only critical in the diagnosis of the COVID-19 infection, on the contrary, but they are also crucial in the prognostic predictions about disease prognosis and therapeutic response. This review aims to give some historical context for the pandemic, demonstrate the laboratory's important role in the screening of COVID-19 infection, and review the current phase of biomarker examination in COVID-19 infection, focusing on markers derived directly from the hematological laboratory, reflecting the implications of COVID-19 on the hematological system and coagulation pathways. In conclusion, there is a direct significant correlation between infection severity, the death rate in COVID-19 patients, and the low number of either WBCs or a high number of WBCs with a low number of lymphocytes. Copyright This is an Open Access article licensed under a Creative Commons license: Attribution 4.0 International (CC-BY). Published by Oriental Scientific Publishing Company © 2022.