COVID-19 Pandemic: Current Scenario, Challenges and Future Perspectives

Abstract

Background: The new public health emergency of COVID-19 caused by a novel Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), which originated in Wuhan, Hubei province, China in December 2019, evolved into a pandemic in no time and is still in progression. The novel virus mainly targets the lower respiratory system, leading to viral pneumonia, with other associated complications of multi organ failure. Discussion: The bats, in particular Rhinolophus affinis, is a natural host of SARS-CoV-2 and the virus is considered to have spread to humans through yet controversial intermediate host pangolins. The incubation period ranges from 2-14 days and mode of person-to-person transmission is primarily via the direct contact with the infected person or through the droplets generated by the infected person during coughing or sneezing. The initiation of the infection process by SARS-CoV-2 virus is the invasion of lung type II alveolar cells via a receptor protein called angiotensin-converting enzyme 2 (ACE2) present on the cell membrane with glycosylated spike (S) viral protein that mediates host cell invasion. The main diagnostic tools employed are molecular methods based on nucleic acid detection engaging real-time quantitative polymerase chain reaction (RT-qPCR) and a new immunoassays based on antibodies IgM/IgG. Conclusion: Due to the lack of specific clinically approved anticovid-19 drugs or vaccines that could be used for its prevention or treatment, the current management approach is essentially supportive and symptomatic. The precautionary measures like, social distancing, cleaning hands with soap or sanitizers, using disinfectant solutions to decontaminate the surfaces of things and proper ventilation, wearing masks and other protective gears to curb transmission. The knowledge regarding COVID-19 therapies is still evolving and collaborative efforts are being put in to discover definitive therapies on different themes in the form of vaccines, repurposing drugs, RNA interference, docking studies, etc.