COVID-19, SARS and MERS: are they closely related?

N Petrosillo; G Viceconte; O Ergonul; G Ippolito; E Petersen

doi:10.1016/j.cmi.2020.03.026

COVID-19, SARS and MERS: are they closely related?

Clin Microbiol Infect. 2020 Jun;26(6):729-734. doi: 10.1016/j.cmi.2020.03.026. Epub 2020 Mar 28.

Authors

N Petrosillo¹, G Viceconte², O Ergonul³, G Ippolito⁴, E Petersen⁵

Affiliations

¹ National Institute for Infectious Diseases 'L. Spallanzani', IRCCS, Rome, Italy. Electronic address: nicola.petrosillo@inmi.it.
² University 'Federico II', Department of Clinical Medicine and Surgery, Naples, Italy.
³ Koc University, School of Medicine, Istanbul, Turkey; ESCMID Executive Committee, Switzerland.
⁴ National Institute for Infectious Diseases 'L. Spallanzani', IRCCS, Rome, Italy.
⁵ Directorate General for Disease Surveillance and Control, Min of Health, Muscat, Oman; ESCMID Emerging Infections Task Force, ESCMID, Basel, Switzerland; Institute for Clinical Medicine, Faculty of Health Sciences, University of Aarhus, Denmark.

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 (2.0-2.5) is still controversial. It is probably slightly higher than the R₀ of SARS (1.7-1.9) 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.

Keywords: COVID-19; Coronavirus; Emerging infections; MERS; SARS.

Publication types

Review

MeSH terms

Basic Reproduction Number
Betacoronavirus / genetics*
COVID-19
Coronavirus Infections / complications*
Coronavirus Infections / epidemiology*
Coronavirus Infections / mortality
Coronavirus Infections / transmission
Humans
Pandemics
Phylogeny
Pneumonia, Viral / complications*
Pneumonia, Viral / epidemiology*
Pneumonia, Viral / mortality
Pneumonia, Viral / transmission
SARS-CoV-2
Severe Acute Respiratory Syndrome / complications
Severe Acute Respiratory Syndrome / epidemiology*
Severe Acute Respiratory Syndrome / mortality
Severe Acute Respiratory Syndrome / transmission
Severe acute respiratory syndrome-related coronavirus / genetics
Virus Attachment