Overview of COVID-19 Pandemic: Transmission, Epidemiology and Diagnosis

In the early part of the last month of the year 2019, suddenly many people started suffering from a new respiratory disease in the city of Wuhan in China. At that time the cause of the disease was not known. The disease was caused by a new coronavirus which was never detected in the past. WHO called it the novel coronavirus 2019. Later the virus was named as severe acute respiratory syndrome coronavirus 2. The disease is considered to have originated from the wet market located in the city of Wuhan in China. It came from the bats and infected the humans and possibly with an intermediate host like the pangolins. From the place it originated the disease spread to other places within China and to other countries outside China. WHO recognised the disease as a pandemic, as the disease spread to other parts of the world in Europe and Asia. This pandemic has affected the mankind as never before. More than 110 million people are confirmed infected with this disease. More than 2.5 million people have succumbed to this devastating disease. The pandemic has affected almost all the countries in the world. At a time when many countries were in lockdown mode, it seemed the world had come to a standstill. Individuals of both sexes belonging to all age groups can get infected, although old persons and persons with co-morbid conditions are more prone to get infected and also has more chance to develop severe form of this disease carrying high morbidity and mortality. In this review, the literature of the causative agent, epidemiology, mode of transmission, diagnosis and treatment and preventive strategies are reviewed, so that the reader is provided with sufficient current knowledge about this disease.