COVID19 Asymptomatic Spread: Still a thing?
As we know, most transmission happens at home. The following paper is a meta-analysis of studies on “household secondary transmission”, n=77,758. This paper was released to the pre-print server on Aug 1, 2020; it was finally published in December 2020. No rush on that global pandemic data, boys. Take your time. After all, we have an election to win.
A total of 54 relevant studies with 77 758 participants reporting household secondary transmission were identified. Estimated household secondary attack rate was 16.6% (95% CI, 14.0%-19.3%), higher than secondary attack rates for SARS-CoV (7.5%; 95% CI, 4.8%-10.7%) and MERS-CoV (4.7%; 95% CI, 0.9%-10.7%). Household secondary attack rates were increased from symptomatic index cases (18.0%; 95% CI, 14.2%-22.1%) than from asymptomatic index cases (0.7%; 95% CI, 0%-4.9%), to adult contacts (28.3%; 95% CI, 20.2%-37.1%) than to child contacts (16.8%; 95% CI, 12.3%-21.7%), to spouses (37.8%; 95% CI, 25.8%-50.5%) than to other family contacts (17.8%; 95% CI, 11.7%-24.8%), and in households with 1 contact (41.5%; 95% CI, 31.7%-51.7%) than in households with 3 or more contacts (22.8%; 95% CI, 13.6%-33.5%).
So if I have this right, if you have an asymptomatic case in your household, you have an 0.7% chance of getting sick; if you have a symptomatic case, your chance of catching the “ro” rises to 18%.
Is asymptomatic spread a thing? Yes – but a very tiny thing. By a factor of 26, it is symptomatic people who do the heavy lifting on transmission at home. Which is where most transmission happens.
Dave’s new rule: “only symptomatic people should be required to wear masks.” (*)
(*) And this assumes masks work. More on that later.
Dr. Marik’s information is very clear. The highest viral load in someone who will be sick tends to be just prior to symptoms. Presymptomatic. That’s a subset of asymptomatic. Probably more important outside the household where the exposure is more temporary.
More interesting than the Stanford University study that shows face masks are not helpful in preventing the transmission of Covid is the fact that Twitter has banned mention of the study…..
From today’s rant on Dr. Vanden Bossche’s site (half way through):
Asymptomatically infected people “are the major spreaders when people get massively vaccinated with vaccines that only protect against disease”.
The paper I quoted above differentiated between the viral load and the propensity of someone to infect someone else. They are – apparently – not the same thing at all. (Who knew? Not me.)
Apparently, just because you have a lot of virus in your system doesn’t mean you will spread it to someone else. Apparently, coughing is a whole lot more effective than breathing out in terms of transmission.
The paper looked at contact-tracing studies in real life. Real people, infecting other real people. How many? Under what conditions?
According to the data they collected, mostly, people didn’t get it from asymptomatics. They got it from symptomatic people. And the difference was massive.
I’ll take that sort of study (real people getting other real people sick) vs viral load which are interesting, but are ultimately theoretical. Simply having a high viral load doesn’t necessarily result in an infection. You could theorize that it might. And it even might prove to be true. But that’s not the same thing as checking out what really happens in real life.
Turns out, coughing >> exhaling.
I didn’t think about this before reading this paper.
If you have an hour, perhaps you could read the paper too? And then we can talk?
Fauci already let the cat out of the bag when he told us that masks were only “symbolic” and did very little [ if anything ] to reduce the spread of covid.
I also believe that the masks are the most critical point in this entire covid issue. Masking is the lynch pin, the ‘spear point’ driving the entire hoax. You get rid of the masks and the whole issue will recede and dissolve into nothing.
Thats why I’ve made it my focus to not wear the mask unless Im absolutely required to. Anywhere I go, stores, public buildings etc, I go maskless. I’ll only put it on if somebody in charge asks me too. Ive been doing this for quite a while and so far only one or two people have ever asked. A couple of days ago I walked right into a large supermarket, right past the “mask security” person [ who pretended not to see me ], and did my entire shop without the mask.
People noticed, and I think thats the point. People have to see others without the mask. Being a generally law abiding person who doesnt like conflict I do feel slightly uncomfortable sometimes going against the grain, but thats a minor sacrifice. Considering that people have fought and died for a little bit of freedom, the least I can put up with is mild social discomfort.
Maybe if we all buck up and face a little bit of inconvenience and discomfort, our children [ or grand children ] wont have to die to reclaim some of the freedoms that we were too timid to assert.
Dave, what you say makes complete sense, thank you. That probably also goes to the concern about people singing in each others presence.
Mask wearing by those who are symptomatic concerns me, though. Helpful to those in the immediate vicinity, but meanwhile the person who is sick is rebreathing all this junk.
Sure thing Kat. The singing thing could be a mode too. That Korean church comes to mind. Not sure this meta-study took singing into account. 🙂
This is also (possibly) why mouthwash/gargles and nasal sprays work so incredibly well against the “ro”. SC2 sits there in the nasal passages, doing its thing, but if you drop some chemical onto it relatively frequently, that stops it from replicating.
This should be the basis of (asymptomatic) people getting back to work. Darn! Don’t tell my boss.
You are really on the ball! I watched the new Bossche last night and was noticing that he emphasizes the role of asymptomatic spread going forward. I am not sure exactly what drives this, whether the emergence of more transmissible variants or something else, but it is prominent in his presentation.
As Dave said, it’s now pretty darn clear that singing together in a closed room is the best way to spread this virus.