Coronavirus Disease -2019 (COVID-19) in 2020: A Perspective Study of a Global Pandemic.

Severe acute respiratory syndrome coronavirus (SARS-CoV-2) is responsible for the coronavirus disease- 2019 (COVID-19) pandemic, which was first reported from Wuhan, China, in late 2019. This infection spread to thousands of people globally within a short span of time with a progressive trend to mortality of citizens. Posing a potential public health threat, SARS-CoV-2 progressed from animal-to-human to human-tohuman transmission with symptoms ranging from little or no illness to persons being severely ill and many deaths, confirming two criteria for declaring COVID-19 a pandemic. The disease shows a progressive trend in symptomology, ranging from mild to severe pneumoniae to respiratory and multi-visceral failure that often leads to the death of patients with comorbidity within a short span of time. Intensive research efforts on different aspects of this human pathogen are underway across the globe for elucidating viral transmission routes and the mechanisms employed to overcome host defense responses. Due to the massive infective potential, studies are being carried out to develop effective diagnostics and therapeutic interventions, including re-purposing antivirals and other potential inhibitors. Herein, we describe the taxonomic classification of 'SARS-CoV-2', the structural organization of its genome, its infectivity, transmission, and receptor interaction; and we summarize risk assessment and approaches used for prevention of the infection. Finally, we discuss important aspects of the development of diagnostic tools and therapeutic countermeasures that have the potential to help in controlling the COVID-19 pandemic.

An association between exposure to Middle East Respiratory Syndrome (MERS) and mortality rate of Coronavirus Disease 2019 (COVID-19).

OBJECTIVE: Our objective was to find an association between exposure of a population to Middle East Respiratory Syndrome Coronavirus (MERS-CoV) and mortality rate due to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) across different countries worldwide. MATERIALS AND METHODS: To find the relationship between exposure to MERS-CoV and mortality rate due to SARS-CoV-2, we collected and analyzed data of three possible factors that may have resulted in an exposure of a population to MERS-CoV: (1) the number of Middle East Respiratory Syndrome (MERS) cases reported among 16 countries since 2012; (2) data of MERS-CoV seroprevalence in camels across 23 countries, as working with camels increase risk of exposure to MERS-CoV; (3) data of travel history of people from 51 countries to Saudi Arabia was collected on the assumption that travel to a country where MERS is endemic, such as, Saudi Arabia, could also lead to exposure to MERS-CoV. RESULTS: We found a significantly lower number of Coronavirus disease 2019 (COVID-19) deaths per million (deaths/M) of a population in countries that are likely to be exposed to MERS-CoV than otherwise (t-stat=3.686, p<0.01). In addition, the number of COVID-19 deaths/M of a population was significantly lower in countries that reported a higher seroprevalence of MERS-CoV in camels than otherwise (t-stat=4.5077, p<0.01). Regression analysis showed that increased travelling history to Saudi Arabia is likely to be associated with a lower mortality rate due to COVID-19. CONCLUSIONS: This study provides empirical evidence that a population that was at an increased risk of exposure to MERS-CoV had a significantly lower mortality rate due to SARS-CoV-2, which might be due to cross-protective immunity against SARS-CoV-2 in that population because of an earlier exposure to MERS-CoV.