“Evidence that Viruses Cause Disease” — Andrew Kaufman [Part 3]
(Continued at 35:19 in the above video)
(7:25) … So notice what is not in Rivers’ criteria. There is nothing about genetic material, DNA, or RNA mentioned at all. So, in other words, you don’t even have to look at the genetic material in order to prove these criteria … (7:41)
And at least formally, the genetic material or specific sequences does not have a role in proving that a virus causes a disease.
(7:49) And I’m following — this is what is specified in the authors of the Nature paper. So, I went and looked at Rivers’ article from 1937 that where he laid out these six criteria and I found a few interesting quotes to help us learn a little bit more detail what he was saying.
(8:09) So the first quote, “…Now it is possible to bring excellent evidence that an organism is the cause of a malady without complete satisfaction of Koch’s postulates.”
(8:19) So basically he’s saying that you can skip the steps that are not included in his criteria and still prove that the virus causes a disease.
(8:28) Next quote is, “…Particularly those diseases caused by viruses, the blind adherence to Koch’s postulates may act as a hindrance instead of an aid.”
(8:39) Well, I think this indicates that he may have been looking for a little bit of a shortcut — that, maybe it was difficult to perform some of the steps, and this makes it a little bit easier to prove a virus is the cause of disease.
(8:53) And it’s not good to let your outcome affect your reasoning when determining these things, but I’ll still accept the Rivers criteria as valid.
(9:01) He said, “It is obvious that Koch’s postulates have not been satisfied in viral diseases.”
(9:05) Now granted, this was in 1937, but up to that time, that was certainly as true as it is today.
(9:10) He also said, “In the first place it is not obligatory to demonstrate the presence of a virus in every case of disease produced by it.”
(9:19) Now, I really don’t understand the reasoning behind this, because if the virus is not present, then how could you say it caused the disease?
(9:28) But, once again I’ll accept these criteria since this is what the author has laid out.
(9:34) And the last quote, “Viruses, whether they are parasites or fabrications of an autocatalytic processes are intimately associated with host cells…”
(9:43) So, this is really important because it indicates a degree of uncertainty³ about the nature of viruses.
(9:51) And when he says that they are fabrications of autocatalytic processes, what I think that means is what’s called “apototic bodies.” So, our cells undergo this programmed cell death called apotosis, and this happens in response to various things. It could just be a natural occurrence, but if there is a major illness the cells might undergo this process and they basically fragment into little “blebs,” and these little bodies I think or what he’s calling the fabrications of an fabrications of an autocatalytic process.
(10:23) But that’s very different from a virus, because that actually comes from our own cells rather than from outside, and he definitely points out the “intimate association” with the host cells which is very important in the experimental methods that I’ll get into.
(10:40) He also said something very important about how you prove the criterion where where you put the isolated virus into a healthy person and caused the same disease and what he said is, “…by means of inoculation of material obtained with patients with the natural disease.”
(10:58) Okay, so not something made in a laboratory, or from a laboratory but “from another patient with the natural disease.” That’s very important.
(11:06) He also said, “If the inoculated animals become sick or die in a characteristic manner” — which means “having the same symptoms as the original disease” — “and, if the disease in them can be transmitted from animal to animal by means of inoculations with blood or emulsions of involved tissue free from ordinary microbes or rickettsiae” — so, in other words, “give them a bodily fluid that has been filtered so that there are no other organisms in that that can confuse the issue (it has to be purified)” — says “one is fairly confident that the malady is the experimental animals is induced by a virus.”
(11:43) So, basically what he’s saying is, if you apply his criteria, it’s not certain, but you can be fairly confident that the virus causes that disease. So that is not very inspiring of confidence in me but nonetheless that is what he said about these criteria.
(11:58)So, in other words even if all six of the criteria are satisfied that only leads you to be fairly confident. Not “conclusive,” not “certain,” not “a hundred percent,” just “fairly confident.”
{Continued in Part 4}
[3] “Associated with” means there is a correlation, not a cause. -LMK
