Introduction to SARS-CoV2:
This post was written on March 22nd, 2020, but news and research on this virus moves fast, and so this information, while accurate at the time of writing, may have changed. As this outbreak continues, we will try to update our posts regularly to maintain accuracy!
Meet SARS-CoV2: aka. SARS2, 2019-nCoV, novel Coronavirus, and cause of COVID-19.
Modified from Harcourt et al., 2020. bioRxiv 2020.03.02.972935; doi: https://www.biorxiv.org/content/10.1101/2020.03.02.972935v2
This is an electron micrograph image of SARS-CoV2 virus particles budding from (leaving) infected tissues. Electron microscopy is a classical way to actually “see” viruses, which are otherwise far too small to image using normal microscopes.
Late in 2019, doctors in the city of Wuhan in China started noticing an unusual number of cases of severe pneumonia in their hospitals. Importantly, the pneumonia was of viral origin (antibiotics, which help against bacteria, were ineffective) and was not caused by influenza virus. Brave doctors sounded the alarm (more about that in an upcoming post) and by Dec. 31, 2019, Chinese officials alerted the rest of the world to a potential outbreak of a new viral pneumonia. Over the following month, we would learn that this disease was caused by a type of virus that belongs to the Coronavirus family, that it was closely-related to the cause of another viral outbreak in 2003 (SARS-CoV), and that the virus could spread relatively well among humans. Skipping forward to today, we have learned a lot about SARS-CoV2 and the illness it causes, and we continue to gather and integrate more information hourly during the worldwide effort to contain this pandemic. SARS-CoV2: The Virus
So, let’s start with the virus. We'll follow up with a more in-depth post about coronaviruses and SARS-CoV2 itself later, but what's helpful to know is that coronaviruses, like many RNA viruses, are messy when they replicate, which means that they change relatively easily. This is probably what let SARS-CoV2 successfully transmit from its original animal host to a human, and what let this virus spread well among humans as well. 
SARS-CoV2 infects humans through the respiratory tract - that is, it gets to your body through your mouth, nose, and even eyes. It infects cells in the respiratory tract as in the picture above (made by BioRender), and hijacks everything the cell normally does to make more copies of the virus. Those new viruses spread and amplify in your lungs, and when you cough, or sneeze, or even talk, you can release new viruses into the environment. These viruses can be spread to others by them inhaling particles (above), but they can also be spread by touching surfaces or objects that an infected person touched earlier, and then touching your mouth, nose, or eyes:I made a fancy infographic, but truthfully, Scrubs did a much better job of visualizing respiratory virus spread by “fomites”, or un-infected objects that can still spread the virus.
COVID-19: The Illness
SARS-CoV2 infection can lead to an illness that doctors and researchers call COVID-19 (COronaVIrus Disease of 2019).
COVID-19 is a collection of symptoms that are hallmarks of infection with this virus. More about the details and less-common symptoms to come, but some of the most common symptoms are:FeverCoughDifficulty breathing
If you think you might have COVID-19, the Government of Canada has provided a self-assessment tool for Canadians, and the CDC has provided a self-checker for Americans. Other public health agencies worldwide are rolling out similar tools. These tools can help you decide whether you should seek testing, but if you are uncertain, you should call a doctor. COVID-19 symptoms can occur at any time between 2 and 14 days after exposure to the virus.Please note that symptoms such as:
Trouble breathing
Persistent pain or pressure in the chest
New confusion or inability to arouse
Bluish lips or face
Are an emergency, and you should call emergency services immediately.
SARS-CoV2: The Epidemiology
SARS-CoV2 poses a high risk of severe infection, hospitalization, and death to people over the age of 60, but younger, otherwise-healthy people also get severely ill at a much higher rate than occurs with other respiratory infections like influenza. SARS-CoV2 poses an additional challenge to public health because along with the severe infections, it can also cause relatively mild infections that can be mistaken for a cold, and even infections with no apparent symptoms at all. People with mild or no symptoms can still spread the virus.
Taken together, this is where social distancing and quarantine measures become extremely important to contain and reduce infection, and protect those who are particularly vulnerable.
Courtesy of Toby Morris (@XTOTL on Twitter) via TheSpinoff.co.nz, this is how individuals affect the course of a pandemic - in their own communities, and worldwide.
One final aspect of the epidemiology of COVID-19 is a phrase that most have heard many times over, “flattening the curve.” This phrase, and various accompanying graphs, pictures, and infographics, is used to help explain why we should take drastic measures like social distancing, closing schools, and reducing hours or closing most retail stores. What do we really mean?
We have observed the consequences of rapid, unchecked spread in places like Wuhan and the Hubei province in China, or northern Italy in Europe:
overcrowded hospitals
depleted stocks of masks, gloves, and respirators
healthcare professionals falling ill
When this occurs, human lives are lost. Thus, the goal is to slow down the spread of infection so that hospitals and staff never get overwhelmed. This ensures that every patient receives maximum care and attention, and this also ensures that our human resources - doctors, nurses, and aides - stay healthy and are able to take action.
Via Dr. Siouxsie Wiles (@SiouxsieW on Twitter) for TheSpinoff.co.nz. The goal is to control virus spread so that the healthcare system - hospital bed capacity, staffing, equipment, and disposables - always has the resources to handle the incoming cases.
COVID-19: Your Actions Matter
This is it. This is why we are providing you with all the information we can, and are trying to give you the tools to evaluate information that you come across online, on the news, and through social media.
Your actions matter.
Not a direct quote.
Until every person can be tested, it is possible that you are infected with SARS-CoV2, but that you don’t have symptoms. Even without symptoms, you also may be able to pass the virus on to more vulnerable people who do get sick from the infection.
Public health officials are asking you to behave as if you were infected, and want to prevent passing the virus on to other people.
Because SARS-CoV2 is an entirely new virus, there are no vaccines, and no FDA-approved drugs that can be used to prevent infection and spread of the virus. Instead, public health workers are seeking to contain the spread of SARS-CoV2 in the most old-fashioned way we know: if you don’t come into contact with the virus, you can’t get infected!
This involves social distancing for uninfected people, quarantine for people with suspected infection, and isolation for people known to be infected. This also involves everyone adopting “mechanical” and chemical measures to control the virus by disinfecting contact surfaces regularly and frequent hand-washing (how and why).
For the best general advice on how you can achieve social distancing, check out your local public health agency’s websites - e.g. the Public Health Agency of Canada:
And visit the CDC’s website for how you can manage your home and outside activities safely, limiting the risk of contracting and spreading infection.
Remember that it can take up to two weeks from the time you were infected, to when you start to show symptoms of infection, and you may be able to infect others during that “silent” time. This is why it is so important for everyone to practice social distancing, even if they feel well themselves.
COVID-19: The Myths
Over the coming days, we will be posting about some common (and less common) myths and misinformation flying around on social media, and even in the news.
Until then, some helpful guidelines:
Go to the source - a scientific paper, or a public health agency’s announcement - to verify the information
Note that many scientists are posting information on a website called BioRXiv (pronounced Bio Archive) for quick dissemination. While most of this information is likely accurate, it has not been peer-reviewed, and you don’t have to be a scientist to post information there. Read those posts with some caution.
Ask an expert - virologist, epidemiologist, or doctor - if you are unsure.
Make medical decisions based on advice from your doctor, not the internet or a friend.
Follow the recommendations of your local public health agencies, since they are tailored to the situation in your area.
Finally, watch these pages for more information. Thank you for reading, and our best wishes to you and your loved ones.
Patricia Thibault, PhD
Patricia hails from Canada and received her PhD from the University of Saskatchewan in 2014, where she studied Hepatitis C Virus (HCV). From 2014-2020 she was a postdoctoral fellow in Dr Benhur Lee’s lab at Mount Sinai where she studied a wide variety of paramyxoviruses. She is currently a research assistant in Dr. Michael C. Levin’s lab in the Department of Anatomy, Physiology, and Pharmacology in the College of Medicine at the University of Saskatchewan.
Twitter: @escape_mutant