About 150 years ago, scientists painstakingly constructed a set of principles that can prove whether a particular microbe is the cause of a specific disease or is just a bystander. Those three principles are known as the Koch postulates.
From all the available information, the novel coronavirus doesn’t appear to meet any of these tenets, never mind all three.
Like most human endeavours, the Koch postulates were the product of collaboration. First, Jakob Henle developed the underlying concepts, and then Robert Koch and Friedrich Loeffler spent decades refining them until they were published in 1890. The resulting three postulates are:
- The pathogen occurs in every case of the disease in question and under circumstances that can account for the pathological changes and clinical course of the disease.
- The causative microorganism occurs in no other disease as a fortuitous and nonpathogenic parasite.
- After being fully isolated from the body and grown in tissue culture (or cloned), it can induce the disease anew.
The principles have been altered almost beyond recognition by various researchers over the ensuing 130 years. But the changes concomitantly watered down the postulates. That’s why they’re still used today by most researchers seeking to robustly prove or disprove the existence of a pathogen and its exclusive relationship with a particular disease.
There’s an urgent need for scientists to step up and do this conclusively with the novel coronavirus and COVID-19. But, strangely, the fire hose of scientific papers on the virus-disease dyad is only a sickly trickle on this tremendously important aspect of it.
A very straightforward and inexpensive experiment is all that’s needed to prove that the first postulate has been met.
Here’s how to do it. Test blood samples from a large number of people for the novel coronavirus using a test that’s been proven by several non-conflicted third parties to be accurate – i.e., to have very low rates of false positives and false negatives.
Then, if all the people who are diagnosed with COVID-19 are the same ones who tested positive for the novel coronavirus, that would prove the virus causes COVID-19. (Note that COVID-19 would have to be diagnosed based on a well-defined and finite set of symptoms. The currently-used and excessively broad diagnostic criteria – such as pneumonia, or the combination of fever and cough – doesn’t cut it, because those are present in many other respiratory conditions.)
But such an experiment has never been done, or if it has been done it hasn’t been made public.