What do we know about the SARS-CoV-2 coronavirus?

The word “coronavirus” has been everywhere for several weeks. But what do we know about it? Thomas Michiels, Professor at UCLouvain and researcher in Molecular Virology at the Duve Institute, reveals the origins of this virus that no one can ignore anymore.

Kings of viruses

Coronaviruses are viruses surrounded by a membrane called an "envelope." This envelope is bristling with glycoproteins which form protrusions on the surface of the virus, called spicules (or "spikes"). In electron microscopy, the spiky envelope gives the virus the appearance of a crown, hence its name of coronavirus. This envelope, which is necessary for infection of cells by the virus, is made up of a membrane of phospholipids, which makes the virus particularly vulnerable to detergents and desiccation. This explains the recommended hand hygiene measures to limit the transmission of the virus. The genetic information in this virus is an RNA molecule with a positive polarity of around 30,000 nucleotides. It is one of the largest RNA viruses.

Human coronaviruses, agents of respiratory infections

Several coronaviruses (such as HCoV-229E or HCoV-OC43) are regularly responsible for respiratory infections in humans. These infections are most often mild (simple colds) but can sometimes be serious in particularly sensitive people, especially immunocompromised people.

Viruses that spread from animals to humans

In 2002 the epidemic of SARS (Severe Acute Respiratory Syndrome) broke out, a coronavirus originating from certain bats which is said to have been transmitted to humans via the civet. More recently in 2013, another bat coronavirus, named MERS (Middle East Respiratory Syndrome), appeared in the Middle East and is occasionally reported to be transmitted to humans via dromedaries. The risk of mortality in this case is very high. The coronavirus that appeared in Wuhan last December was called SARS-CoV-2, the nucleotide sequence of its genome having identified it as a close cousin of the SARS virus. The disease induced by SARS-CoV-2 has been called Covid-19. As in 2002, the virus is also believed to originate from the bat, but this time would have passed through the pangolin to reach us.

Covid-19 and its symptoms

Symptoms of the disease are mainly fever, cough and difficulty breathing. Unlike the coronaviruses conventionally encountered in humans, which most often remain confined to the upper respiratory tract, the Covid-19 virus would, like the SARS virus, have a certain tropism for the lower respiratory tracts, which explains why it is sometimes responsible for serious pneumonia.

To find out more about SARS-CoV-2 and the Covid-19 pandemic, please find below all of Thomas Michiels' interventions in the media:

ScienceToday - Broad spectrum antivirals: a complicated mission … but not impossible! - 29/04/2020

EN24.news - “Globalization worsens the pandemic” say scientists to the president of the MR - 1/04/2020

RTBF.be - Une même mutation chez les variants britannique et sud africain, ou la loi du plus fort parmi les lignées du coronavirus - 5/02/2021

FemmeActuelle.fr - Covid-19 : le régime alcalin peut-il vous protéger du virus ? - 29/10/2020

Factuel.AFP.com - Reconnaître et "éliminer" le Covid-19 : attention, cette publication contient de fausses affirmations - 28/10/2020

EnMarche.be - Les virus, ces drôles de (fausses) petites bébêtes… - 20/05/2020

RTBF.be - Les appareils à UV pour désinfecter, une solution miracle ? - 19/05/2020

Moustique.be - Covid-19: des symptômes toujours plus nombreux - 23/04/2020

LeVif.be - Les experts de l'UCLouvain vous répondent : "Une piste pour lutter contre ces infections" - 20/04/2020

L'avenir.net - Le coronavirus : bien au-delà d'une insuffisance respiratoire - 17/04/2020

RTBF.be - "La distanciation de 1m50, c'est de la foutaise" : vrai ou faux ? - 16/04/2020