a narrative review of covid-19: the new pandemic disease

Nearly every 100 years, humans collectively face a pandemic crisis. after the spanish flu, now the world is in the grip of coronavirus disease 2019 (covid-19). first detected in 2019 in the chinese city of wuhan, covid-19 causes severe acute respiratory distress syndrome. despite the initial evidence indicating a zoonotic origin, the contagion is now known to primarily spread from person to person through respiratory droplets. the precautionary measures recommended by the scientific community to halt the fast transmission of the disease failed to prevent this contagious disease from becoming a pandemic for a whole host of reasons. after an incubation period of about two days to two weeks, a spectrum of clinical manifestations can be seen in individuals afflicted by covid- 19: from an asymptomatic condition that can spread the virus in the environment, to a mild/moderate disease with cold/flu-like symptoms, to deteriorated conditions that need hospitalization and intensive care unit management, and then a fatal respiratory distress syndrome that becomes refractory to oxygenation. several diagnostic modalities have been advocated and evaluated; however, in some cases, diagnosis is made on the clinical picture in order not to lose time. a consensus on what constitutes special treatment for covid-19 has yet to emerge. alongside conservative and supportive care, some potential drugs have been recommended and a considerable number of investigations are ongoing in this regard.