COVID-19: A Global Challenge with Old History, Epidemiology and Progress So Far

Abstract

Humans have witnessed three deadly pandemics so far in the twenty-first century which are associated with novel coronaviruses: SARS, Middle East respiratory syndrome (MERS), and COVID-19. All of these viruses, which are responsible for causing acute respiratory tract infections (ARTIs), are highly contagious in nature and/or have caused high mortalities. The recently emerged COVID-19 disease is a highly transmittable viral infection caused by another zoonotic novel coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Similar to the other two coronaviruses such as SARS-CoV-1 and MERS-CoV, SARS-CoV-2 is also likely to have originated from bats, which have been serving as established reservoirs for various pathogenic coronaviruses. Although, it is still unknown how SARS-CoV-2 is transmitted from bats to humans, the rapid human-to-human transmission has been confirmed widely. The disease first appeared in Wuhan, China, in December 2019 and quickly spread across the globe, infected 48,539,872 people, and caused 1,232,791 deaths in 215 countries, and the infection is still spreading at the time of manuscript preparation. So far, there is no definite line of treatment which has been approved or vaccine which is available. However, different types of potential vaccines and therapeutics have been evaluated and/or are under clinical trials against COVID-19. In this review, we summarize different types of acute respiratory diseases and briefly discuss earlier outbreaks of coronaviruses and compare their occurrence and pathogenicity with the current COVID-19 pandemic. Various epidemiological aspects of COVID-19 such as mode of spread, death rate, doubling time, etc., have been discussed in detail. Apart from this, different technical issues related to the COVID-19 pandemic including use of masks and other socio-economic problems associated with the pandemic have also been summarized. Additionally, we have reviewed various aspects of patient management strategies including mechanism of action, available diagnostic tools, etc., and also discussed different strategies for the development of effective vaccines and therapeutic combinations to deal with this viral outbreak. Overall, by the inclusion of various references, this review covers, in detail, the most important aspects of the COVID-19 pandemic.

Therapeutic effects and safety of oral Chinese patent medicine for COVID-19: A rapid systematic review and meta-analysis of randomized controlled trials

“…4 The SARS-CoV-2, causes acute respiratory tract infections, is highly contagious in nature causing high mortality. 5 The main symptoms of COVID-19 are fever, dry cough and fatigue, and may be accompanied with nasal congestion, runny nose, sore throat, diarrhea, or loss of taste and smell (anosmia). 6 , 7 Almost all of the patients with COVID-19 have pneumonia, and their chest CT scans show abnormalities.…”

Forecast of the outbreak of COVID-19 using artificial neural network: Case study Qatar, Spain, and Italy

“…Different studies have shown that the main concerns related to SARS-CoV-2 are its high transmission potential that has been responsible for the global COVID-19 outbreak [11] , [12] , [13] . The fast-spreading rate of COVID-19 is a result of different transmission methods, including one that is proved to be the most effective: direct contact between humans [14] . This close contact facilitates transmission more rapidly as droplets are expelled through individuals coughing or sneezing [15] , [16] .…”

Retrospective Assessment of Treatments of Hospitalized Covid-19 Patients

“…Despite India's large population it has a lower infection rate than US, and case fatality rate is the lowest among the top four affected countries. [9] Various factors have been ascribed to the relative resistance of Indians to SARS-Cov-2, including BCG, [10] measles-mumps-rubella vaccines, [11] cross and herd immunity [12] and genomics. [13] It is not known whether the guidelines for management of patients issued by Indian authorities and which were revised from time to time based on available evidence was one of the factors.…”