Understanding the unusual viral outbreak: Coronavirus disease 2019

Abstract

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of the respiratory coronavirus disease 2019 (COVID-19). Coronaviruses are a large family of enveloped, positive-sense, single-stranded RNA viruses, which infect a broad range of vertebrate animals. The SARS-CoV-2 is spread primarily between people through close contact and through respiratory droplets produced from coughs or sneezes by the infected individuals. After entering into the human body, it enters human cells by binding to the angiotensin-converting enzyme 2 receptors, prominently present in lung, kidney, and gastrointestinal tract. Older people and people of all ages with severe chronic medical conditions such as diabetes, lung disease, and heart disease seem to be at higher risk of developing serious COVID-19 illness. There have been four pandemics caused by the emergence of new influenza viruses in the past century such as H1N1 Spanish flu (1918), H2N2 Asian flu (1957), the H3N2 Hong Kong flu (1968), and the H1N1 Swine flu (2009). Community interventions are important response strategies that can reduce the impact of disease. Widespread transmission of the virus could translate the situation into large numbers of people needing medical care at the same time. Better understanding of the complexity and dynamics of influenza pandemics reduces the further risk effect of such critical situations. Global efforts in tackling the virus at this time are focused all together on lessening the spread and impact of this virus.