کووید ۱۹، سارس و مرس
Abstract
Introduction
Conclusions
Author contributions
Transparency declaration
References
Abstract
Background: The 2019 novel coronavirus (SARS-CoV-2) is a new human coronavirus which is spreading with epidemic features in China and other Asian countries; cases have also been reported worldwide. This novel coronavirus disease (COVID-19) is associated with a respiratory illness that may lead to severe pneumonia and acute respiratory distress syndrome (ARDS). Although related to the severe acute respiratory syndrome (SARS) and the Middle East respiratory syndrome (MERS), COVID-19 shows some peculiar pathogenetic, epidemiological and clinical features which to date are not completely understood. Aims: To provide a review of the differences in pathogenesis, epidemiology and clinical features of COVID-19, SARS and MERS. Sources: The most recent literature in the English language regarding COVID-19 has been reviewed, and extracted data have been compared with the current scientific evidence about SARS and MERS epidemics. Content: COVID-19 seems not to be very different from SARS regarding its clinical features. However, it has a fatality rate of 2.3%, lower than that of SARS (9.5%) and much lower than that of MERS (34.4%). The possibility cannot be excluded that because of the less severe clinical picture of COVID-19 it can spread in the community more easily than MERS and SARS. The actual basic reproductive number (R0) of COVID-19 (2.0e2.5) is still controversial. It is probably slightly higher than the R0 of SARS (1.7e1.9) and higher than that of MERS (<1). A gastrointestinal route of transmission for SARS-CoV-2, which has been assumed for SARS-CoV and MERS-CoV, cannot be ruled out and needs further investigation. Implications: There is still much more to know about COVID-19, especially as concerns mortality and its capacity to spread on a pandemic level. Nonetheless, all of the lessons we learned in the past from the SARS and MERS epidemics are the best cultural weapons with which to face this new global threat.
Introduction
The 2019 novel coronavirus (SARS-CoV-2) is a new human coronavirus which emerged at the end of December 2019 in Wuhan, China. It is currently spreading with epidemic features in China and other Asian countries, and cases have been reported in Europe, Australia and North America. Currently (as of 8th March 2020) 105 586 confirmed cases have been reported in 101 countries, with a total of 3584 deaths [1]. Coronavirus disease (COVID-19) is the clinical syndrome associated with SARS-CoV-2 infection; it is characterized by a respiratory syndrome with a variable degree of severity, ranging from a mild upper respiratory tract illness to severe interstitial pneumonia and acute respiratory distress syndrome (ARDS) [2e4]. Although SARS-CoV-2 belongs to the same Betacoronavirus genus as the coronaviruses responsible for the severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) (SARS-CoV and MERS-CoV, respectively), this novel virus seems to be associated with milder infections.