BackgroundfactsSARS-CoV-2.pdf

Basic facts regarding SARS-CoV-2, the virus causing the current pandemic
 The name of this virus (which is an organism) is SARS-CoV-2
o SARS-CoV-2 stands for ‘severe acute respiratory syndrome (SARS)-associated coronavirus-2’
 Note: the ‘2’ at name’s end helps to distinguish it from a related virus named SARS-CoV (or
SARS-CoV-1) that caused an outbreak in 2002-2003 (~ 800 confirmed cases, mostly in China).

 The name of the disease that SARS-CoV-2 causes is COVID-19, which stands for ‘Coronavirus disease 2019’. The
symptoms of the disease vary widely among individuals – some have no symptoms (=asymptomatic), while
others have mild, moderate or serious symptoms which generally involve the respiratory tract.

 SARS-CoV-2 is a viral species within the genus Coronavirus. Since there are other species in this genus, many
different Coronaviruses exist. Some Coronaviruses infect humans and can cause serious illness (e.g. SARS-CoV-2,
SARS-CoV-1, and MERS [Middle East Respiratory Syndrome Coronavirus]), whereas other human Coronaviruses
can cause the common cold, which is generally a mild illness (these ‘common’ Coronaviruses are named 229E,
NL63, OC43, and HKU1). Other Coronaviruses aren’t known to infect humans but rather infect other animals.
Often, in the press or in casual conversation, SARS-CoV-2 is referred to as ‘Coronavirus’ or ‘COVID-19’, which is
fine…but, as students taking a college biology course, you should know that there are many different
Coronaviruses, the proper name of this specific one is SARS-CoV-2 and the disease it causes is COVID-19.

 All viruses, including the Coronaviruses, are NOT cells and they can only reproduce when they infect a specific
host cell. Viruses are not considered cells since they lack several structures that all cells have (e.g., ribosomes)
and lack several processes that all cells perform (e.g., make ATP).

 All Coronaviruses use RNA as their hereditary material (= genome) instead of having a DNA genome. You should
think this is weird….remember, the genomes of all cells consists of DNA (not RNA). The RNA genome of a
Coronavirus is stabilized by attached proteins called nucleocapsids (labeled ‘N protein’ below) and is surrounded
by a phospholipid coat called an envelope (in red below). Interestingly, the virus steals these phospholipids
from the host cell it infects!

Source: Wikipedia
Sticking out from the phospholipid envelope, like rays of the sun, are a series of surface glycoproteins (proteins with
attached sugars) termed spikes (in pink above). ‘Corona’ is a Latin term meaning ‘crown’ – makes sense, right? This
viral genus was named Coronavirus since the glycoprotein spikes radiating from the viruses’ surface resemble the spikes
radiating from a crown. Most vaccines candidates currently in clinical trials are designed to expose the body to either
the SARS-CoV-2 spike or a just portion of the spike (neither of which, on their own, are infectious). If successful, the
spike-based vaccine would ‘train’ the body, without causing disease, to generate neutralizing antibodies and long-lived
immune cells that would recognize the real SARS-CoV-2 upon future infections and target the virus for destruction.