Things I should not have to explain in 2020 part 2:

- SARS-CoV-2 exists
- SARS-CoV-2 causes COVID-19

This time, a (long) thread

I think that when people make these claims- these absurd claims- it's not the result of taking a collection of premises, analyzing them, and drawing a parsimonious conclusion (setting aside the preposterousness of that conclusion).

There's this concept in psychology called "locus of control." It refers to the extent to which a person feels in control of what happens to them, as opposed to external forces beyond their influence.

I could think of few things could make our respective loci of control feel more external than this pandemic which has stolen over 1 million lives prematurely and permanently changed life for many more.

What if SARS-CoV-2 didn't exist?

We all crave that normalcy that predates this tempestuous time.

We miss not having to wear masks when we go out. We miss not having to worry about standing too close to people. We miss physical contact. We miss having plenty of surge capacity. We miss not feeling this way.

People need it to not be real.

But denying the existence of SARS-CoV-2, of this pandemic, its scale, its influence- it will only take us further from normalcy. It will only deepen the chasm between where we are and where we one day hope to be.

SARS-CoV-2 was first noticed on 12/31/19 when a cluster of pneumonia associated with Wuhan's Huanan Seafood Wholesale Market appeared.

On 01/09/20, the China CDC reported nCoV-2019 (later renamed SARS-CoV-2) was the cause and its genome was made publicly available.

A more comprehensive history of things can be found here:
https://www.ecdc.europa.eu/sites/default/files/documents/Risk%20assessment%20-%20pneumonia%20Wuhan%20China%2017%20Jan%202020.pdf

Since that time, SARS-CoV-2 has been isolated numerous times:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7045880/pdf/ophrp-11-3.pdf
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7036342/pdf/jkms-35-e84.pdf
https://wwwnc.cdc.gov/eid/article/26/6/20-0516_article
https://jvi.asm.org/content/jvi/94/11/e00543-20.full.pdf
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7140597/pdf/eurosurv-25-13-1.pdf
https://reader.elsevier.com/reader/sd/pii/S2214250920302687?token=4E55EF42D83CCD95187254D7FFD8B7EE8AC0F9B5C1D6D334ABC481FB8CEA65B21B00AB053DA561433F05D38626232383
http://clinicalmicrobiologyandinfection.com/action/showPdf?pii=S1198-743X%2820%2930170-1
etc.

There are additionally multiple animal models that recapitulate (to varying degrees) disease:
https://science.sciencemag.org/content/sci/368/6494/942.full.pdf
https://www.nature.com/articles/s41385-020-00340-z.pdf
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7250783/pdf/main.pdf
https://www.pnas.org/content/pnas/117/28/16587.full.pdf
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7401025/pdf/JEM_20201241.pdf
https://www.nature.com/articles/s41586-020-2324-7 https://science.sciencemag.org/content/369/6505/812

And phylogenies can be constructed of isolates:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7366979/pdf/main.pdf
https://www.pnas.org/content/pnas/117/17/9241.full.pdf
https://nextstrain.org/sars-cov-2/ 
And I offer this one for some good news:
https://www.pnas.org/content/pnas/117/38/23652.full.pdf

Its origin is unambiguously natural based on the best evidence available:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7095063/pdf/41591_2020_Article_820.pdf
https://www.nature.com/articles/s41586-020-2313-x
https://www.nature.com/articles/s41594-020-0468-7
https://www.cell.com/action/showPdf?pii=S0092-8674%2820%2930328-7
https://www.cell.com/cell/pdf/S0092-8674(20)31012-6.pdf

Some denialists have proposed that SARS-CoV-2 is no virus at all, rather it is an exosome.

Exosomes are extracellular vesicles made by cells to communicate with other cells. In principle, they resemble enveloped viruses. Except exosomes are not infectious.

The fact that inoculation of susceptible and permissive cell cultures with SARS-CoV-2 produces cytopathic effects (CPE) and the virus can be isolated and this can be repeated ad infinitum plainly refutes this (the CPE can be viewed in some links above).

Additionally, SARS-CoV-2 has been sequenced repeatedly. Its genome exhibits prototypical features common to coronaviruses and does not align with sequences present in our own genome, ruling out an endogenous origin.

Some denialists also claim that SARS-CoV-2 is not the cause of COVID-19 because something something Koch's postulates (I have not heard a coherent statement of the canard so this is the best I can do in summarizing it).

Koch's postulates 4 conditions that can be used to determine which pathogen (and whether a pathogen) is responsible for a given disease.

However, as is eloquently explained here ( https://www.virology.ws/2010/01/22/kochs-postulates-in-the-21st-century/) these conditions are imperfect and not readily applicable to viruses.

Nonetheless, the fact that COVID-19 occurs in patients who are infected with SARS-CoV-2 and does not occur in those not infected by it is about as iron-clad evidence as any that SARS-CoV-2 is the cause of COVID-19.

I am begging you- stop contributing to the misinfodemic we have at play. It is killing people.
Fact check claims put before you.
Listen to experts.

Wear your mask. Physically distance. Wash your hands.