COVID-19 pandemic: Understanding the emergence, pathogenesis and containment (Review)

Abstract

The ongoing crisis of the novel SARS-CoV-2 disease (COVID-19) has forced several countries to resort to extreme public health measures at a level never encountered in the past century. Originating in Wuhan, China, this is the third highly pathogenic coronavirus (CoV) following SARS-CoV-1 and MERS-CoV. As of June 20, 2020, >8.6 million of the world population were infected with SARS-COV-2, and almost 0.46 million individuals have succumbed to the disease. After 6 months of the outbreak, the understanding of the pathobiology and epidemiology of COVID-19, as well as clinical manage- ment strategies have increased substantially. The phylogenetic analysis of SARS-CoV-2, exhibiting close similarity (~96%) with bat SARS-like CoV has indicated its zoonosis in bats. The human-to-human transmission of COVID-19 has been confirmed through multiple modes, such as nasal droplets, oral mucus, aerosols and fomites. SARS-CoV-2 has an incubation period of 2-14 days with symptoms of fever, cough and breath- lessness, which may manifest from mild pneumonia to severe illness and death. Currently, RT-PCR and antibody-based test kits are being used for the identification of infected indi- viduals. Owing to the lack of specific available treatments, several repurposed drugs and new vaccine candidates are currently undergoing phase I/II clinical trials and are expected to be available to the public as soon as possible. Nonetheless, it is imperative for world bodies to unite in combating this pandemic by developing cost-effective kits and therapeutics, and making them available to resource-poor countries.