Dr. Aaron Glatt on Asymptomatic Transmission, June 2020
Claim: Asymptomatic transmission is a significant driver of covid transmission.
This is part of a series to highlight the ineptitude and sheer illiteracy of the experts my community has relied upon for covid medical advice. I am only employing arguments that can be made from the data/studies and other information available at the time the claim was made.
This rebuttal was written a few days following the publication of Dr. Glatt’s article. It has been lightly edited for grammar and clarity.
Claim: Asymptomatic transmission is a significant driver of covid transmission.
Source: Rabbi Dr. Aaron Glatt COVID-19 Update, June 11, [2020] 9:00 PM
Background: Major lull in covid heading into the summer of 2020.
The Facts
ASYMPTOMATIC TRANSMISSION:
To begin, the WHO stated at the beginning of the covid pandemic:
“Asymptomatic #2019nCoV infection may be rare, and transmission from an asymptomatic person is very rare with other coronaviruses, as we have seen with MERS. Thus, transmission from asymptomatic cases is likely not a major driver of transmission”.
This reflected a (formerly) basic axiom of respiratory viruses, which is that asymptomatic carriers are rarely contagious. This places the burden of proof upon those who wish to claim that covid is truly novel in this regard, to at least show that the observed transmission data, to some degree, can indicate this. The data, however, show no such thing.
“Stealth Community Spread” going way back to January
Firstly, even the CDC has (finally) acknowledged that there was “stealth” community spread going back to early January. (I believe that covid was romping about in December too at a minimum, based on travel numbers, which was always obvious to anyone who cared to think critically.)
This means that there were roughly 10,000 sports-stadium level “mass-gatherings”, and mostly indoors, that had no discernable impact at all whatsoever on covid transmission.
This would also be despite the at-least 35,000,000 cases (per the CDC’s estimations based off of the serology testing at the time), at least some portion of which had to have been running around in January and February, some of whom would have attended these events.
And all of the preceding points don’t even begin to account for the millions of lesser, but still supposedly highly contagious, gatherings (i.e. business meetings).
There is no way that asymptomatic people can be meaningfully contagious yet millions of them didn’t infect anyone, this despite also having thousands of sports games and the like.
Contact Tracing Studies
Secondly, contact tracing from around the world consistently finds that asymptomatic people are not infecting others:
This study (link) found that “all the 455 contacts [of asymptomatic people] were excluded from SARS-CoV-2 infection and we conclude that the infectivity of some asymptomatic SARS-CoV-2 carriers might be weak”.
This study (link) found that 20% of index cases infected 80% in Hong Kong, and 70% of infected people didn't infect anyone.
This study (link) found that 80 percent of transmissions were caused by 8-9 percent of cases.
The same pattern is true in Israel, where a pre-print study (link) found that “between 1-10% of infected individuals resulting in 80% of secondary infections”.
In other words, the vast majority of infected people don’t actually infect anyone (despite having potentially infectious social interactions!).
Another study found that:
“Infection prevention and control guidelines should take into account that patients with severe or critical COVID-19 may shed infectious virus for longer periods of time compared to what has been reported for in patients with mild COVID-19. Infectious virus shedding drops to undetectable levels below a viral RNA load threshold and once serum neutralizing antibodies are present.”
(The authors were typically restrained in their assessment; they only were able to detect virus shedding in 23/129 (17.8%) of the patients studied, all of whom were hospitalized, which would suggest that that there are yet unidentified factors that can prevent shedding even in someone severely symptomatic.)
And yet another study found that
“A study examining 468 confirmed COVID-19 cases in China indicated that only 59 (12.6%) of case reports resulted from presymptomatic transmission. Although this study was also based on secondary data sources, they obtained reliable information from confirmed cases in online reports from 18 provincial centers for disease control and prevention. Perhaps the most convincing study on presymptomatic transmission of COVID-19 was performed in Singapore. Direct contact tracing of 157 locally acquired cases indicated that just 10 (6.4%) of the cases occurred through presymptomatic transmission. Together these studies indicate COVID-19 transmission is 10- to 20-fold more efficient after symptom onset..” And this “Nevertheless, the various coronavirus studies described here indicate that if we focus on one parameter of transmission (pre-symptom vs. post-symptom onset exposure), we find that although presymptomatic transmission of COVID-19 is possible, it appears inefficient compared to transmission after symptom onset.”
It is important to point out that there is a huge difference between pre-symptomatic and asymptomatic. The studies that find transmission in non-symptomatic individuals are all in pre-symptomatic people, meaning that they develop symptoms eventually (usually within 1 or 2 days of infecting someone at most). Genuinely asymptomatic people, on the other hand, do not appear to be contagious at all, or at least to such a miniscule extent that it’s almost impossible to see any indication in case or transmission data.
That the WHO walked back their recent admission that asymptomatic spread is rare - under massive political pressure - does not indicate at all that their initial assessment was wrong, Dr. Glatt’s insinuations notwithstanding. Dr. Glatt does not understand politics, and therefore does not grasp the political nature of the WHO’s actions or statements. (I believe that their initial statement about asymptomatic transmission being rare was itself only put out for political reasons, namely to run cover for the massive Floyd protests/riots that would have otherwise been indefensible.)
Multiple mass gatherings did not lead to any spike in covid cases
Furthermore, there have been quite a few notable mass gatherings (before the recent rioting) that failed to generate any sort of spike at all, including the (in)famous Wisconsin primaries (a few hundred thousand people, no social distancing on those long lines to get into a polling location, etc.), the Lake Ozark parties, and a few others that I can’t remember off the top of my head. (Although the most obvious reason for these is the lack of outdoor transmission generally, there were enough instances of actual physical contact, in addition to the very indoor transportation involved in these events, that should have been enough to be infectious judging by some of the pictures.)
Debunking the junk science cited by Dr. Glatt
Let us now turn to the meta-study cited by RD Glatt from the Annals of Internal Medicine. To begin, they admit that:
“To be clear, the asymptomatic individual is infected with SARS-CoV-2 but will never develop symptoms of COVID-19. In contrast, the presymptomatic individual is similarly infected but eventually will develop symptoms. The simple solution to this conundrum is longitudinal testing—that is, repeated observations of the individual over time. Unfortunately, only 5 of our cohorts include longitudinal data. We must therefore acknowledge the possibility that some of the proportions of asymptomatic persons are lower than reported.”
That’s 5 out of 16. Not a very auspicious start – right off the bat we have them admitting that there may exist a significant degree of entanglement between pre-symptomatic and asymptomatic that is not disentangled in the results. And they admit further in that their data set has other issues that compromise the validity of their results.
The study’s authors further seems to miss all of the studies that I quoted above, and every similar study, also not particularly auspicious. (I have noticed that many researchers aren’t very imaginative when choosing the keywords to use in attempting to survey the existing literature on a subject, and miss lots of otherwise relevant results (that for some reason also seem to always include those most incompatible with what they are about to assert in their paper).)
Anyway, here is the part cited by RD Glatt:
“The early data that we have assembled on the prevalence of asymptomatic SARS-CoV-2 infection suggest that this is a significant factor in the rapid progression of the COVID-19 pandemic. Medical practice and public health measures should be modified to address this challenge.”
This argument is at best blatant speculation. What they are arguing is that “since asymptomatic cases make up such a large % of the covid infections, therefore it follows that they are responsible for an at least somewhat similar % of transmissions”.
There is nothing in their study however that supports the contention that the % of resultant covid infections is indicative somehow of the contagious-cases profile - there is no reason that a minority of the covid cases are responsible for the majority of secondary covid infections and that 40% of covid infections are asymptomatic.
And it certainly does not provide a mechanistic explanation as to why it should be that severely symptomatic individuals are equally contagious with asymptomatic individuals. Citing a solitary study that claimed to discover equal viral loads in asymptomatic and symptomatic (this part was not quoted above) - an astounding observation to say the least, and one that the study does not bother to offer an explanation for - to promote a revolutionary assertion is rank negligence for a peer-reviewed paper.
More importantly, this contention is refuted by the numerous contact tracing studies (that do not suffer from the plethora of self-identified analytical shortcomings within their data sets as does this study), which all show that a small minority – as in 9-20% - are responsible for >80% of infections - the opposite of what the authors of this study decided to just assume without evidence!!
This study is simply not authoritative whatsoever, nor even remotely significant, in attempting to determine the degree of asymptomatic contagiousness.
Dr. Glatt’s reliance on this “study” to provide an evidentiary basis for the claim that asymptomatic transmission is potentially a significant transmission vector is itself asymptomatic of the elementary scientific rigor that ought inform such weighty proclamations.
I can go on about this, but this should be sufficient to make the case. I will say that there were no competent studies that I was aware of then that purport to show that genuinely asymptomatic transmission (as opposed to pre-symptomatic) is a significant covid transmission vector.
Asymptomatic transmission has since become a significant driver in vaccinated people, because the vaccines can blunt or eliminate covid disease symptoms without reducing the viral load of covid infection, something that does not typically occur naturally.