Why it matters where COVID came from
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Pandemics will keep showing up regardless of if they're engineered or natural. It may be a 100% antibiotic-resistant bacteria next time, or some weird prion thing no-one thought about before, or the T-virus, or whatever's floating in the atmosphere of Venus. Who knows.
If we learn to correct what we're doing right now, then even if this happens again from a completely novel threat vector we didn't anticipate, we can handle it quickly and effectively.
The genome was sequenced increadibly quickly, and much of the vaccine work is based on all of the research that went into dealing with SARS 20 or so years ago.
A pandemic caused by something completely novel- whether a contageous and infectious prion disease (does that even make sense?) Or T-virus or venus flu- means that there will be far greater uncertainty than what we have been dealing with. A vaccine wouldn't even make sense in the case of a pandemic prion disease.
I think that Sweden had the right of things, but as others have pointed out before (and likely will again) it is still too early to tell. Not only that, but complicating matters is that every country captures statistics differently- especially the US and UK versus Europe. Numbers get bandied about quite a bit, and I suspect it will be many years before cool heads can evaluate all of the confounding factors into what actually helped and what we should do in the future.
Edit: Hang on, why couldn't you make a vaccine against a prion? I can't see why it's not possible theoretically.
are there even treatments for any prion diseases? for BSE/mad cow disease, they killed millions of cows. to this day, if you're from/were in the UK during the outbreak, you can't give blood in quite a few countries.
and - surprise! - apparently prions could be spread via the air [0]. but it isn't clear how this could occur naturally, so at least that's good news.
"Here, we report a novel experimental strategy for preventing prion disease based on producing a self-replicating, but innocuous PrPSc-like form, termed anti-prion, which can compete with the replication of pathogenic prions."
"...a prophylactic inoculation of prion-infected animals with an anti-prion delays the onset of the disease and in some animals completely prevents the development of clinical symptoms and brain damage."
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5738294/
So that's more good news.
Edit: Hold on, that's the paper you were talking about, right? I didn't make the connection until just now.
Just as much as we learned those lessons from dealing with the spanish flu.
As one of my friends said, people doesn't learn, unless one of their relatives or close friends die. Until then they complain about having to wear a mask or missing out the prom ball.
There are enough people on this earth to be able to focus on more than one question.
It used to be assumed that N95, especially unfitted, had an effectiveness between 0-50%. And that surfaces play a large role in transmissions.
It's increasingly obvious that neither are true.
Hell, the CDC came out and said the epidemic might be over after 4-6 weeks of universal mask usage. And that masks may be more effective than the vaccine. Thats hyuge, and shows just how idiotic certain people in the US government were with initial guidance on masks.
https://www.who.int/emergencies/diseases/novel-coronavirus-2...
>Non-medical, fabric masks are being used by many people in public areas, but there has been limited evidence on their effectiveness and WHO does not recommend their widespread use among the public for control of COVID-19.
Further reading:
https://www.who.int/publications/i/item/advice-on-the-use-of...
>Many countries have recommended the use of fabric masks/face coverings for the general public. At the present time, the widespread use of masks by healthy people in the community setting is not yet supported by high quality or direct scientific evidence and there are potential benefits and harms to consider
>Results from cluster randomized controlled trials on the use of masks among young adults living in university residences in the United States of America indicate that face masks may reduce the rate of influenza-like illness, but showed no impact on risk of laboratory-confirmed influenza.(62, 63) At present, there is no direct evidence (from studies on COVID- 19 and in healthy people in the community) on the effectiveness of universal masking of healthy people in the community to prevent infection with respiratory viruses, including COVID-19.
The whole PDF is worth a read, especially the "Guidance on the use of masks for the general public", and is the most recent guidance from WHO about mask use.
"However, for areas of widespread transmission, with limited capacity for implementing control measures and especially in settings where physical distancing of at least 1 metre is not possible – such as on public transport, in shops or in other confined or crowded environments – WHO advises governments to encourage the general public to use non-medical fabric masks."
Sounds to me like although they don't have 100% gold-standard RCT evidence to say that cloth masks reduce transmission by this %, they still see it as the single best method to prevent spread of the virus under 'real-world' conditions.
>single best method
On the contrary, it's literally the worst out of all the measures they recommend, like physical distancing and hand washing.
"However, taking into account the available studies evaluating pre- and asymptomatic transmission, a growing compendium of observational evidence on the use of masks by the general public in several countries, individual values and preferences, as well as the difficulty of physical distancing in many contexts, WHO has updated its guidance to advise that to prevent COVID-19 transmission effectively in areas of community transmission, governments should encourage the general public to wear masks in specific situations and settings as part of a comprehensive approach to suppress SARS-CoV-2 transmission (Table 2)."
The later stuff is on filtration by cloth masks. I don't think that's why cloth masks are effective.
They're terrible filters. Don't think of cloth masks as filters. N95 does that, but cloth masks are useless for that.
What they do is alter the trajectory of respiratory droplets coming out of your mouth.
When you talk, your vocal cords vibrate, and that aerosolizes tiny liquid droplets from your respiratory tract. These droplets may contain viral particles.
When you wear a cloth mask, you're not filtering out those particles, you're altering their trajectory.
With the cloth barrier, the droplets catch on the mask, or are deflected at an angle that is not straight-ahead at the level of other people's mouth.
So if everyone is wearing masks, then it disrupts the vectors of virus-containing droplets being directed from one person's mouth directly into another person's airway, especially during vocalization.
The redirected particles spent more time in the air, and so have more of a chance to dry out before being inhaled.
It's one-big harm-reduction strategy, where the goal is not to completely filter out viral particles, but rather to make sure that you're not directly inhaling too many on a given exposure (sub-infectious dose).
That's how I think of it. There's no RCT or anything that proves it, but I haven't thought of any good argument for why this isn't a good model for what's going on.
Although hand-washing and physical distance are the gold-standard, part of the problem is that it doesn't seem to be feasible as an option (at least in the US), so we need to rely more heavily on the single best harm-reduction strategy, which seems to be masks at the moment. It's the difference between the best option in a lab, and the best option in a crowded grocery store or subway train where people aren't necessarily going to follow the rules.
To clarify, you said "With the cloth barrier, the droplets catch on the mask, or are deflected at an angle" -- I'm saying that "catch on the mask" is precisely the filtration efficiency noted above, and "deflected" doesn't matter if they're just hanging in the air for several minutes, <30cm from head level (even in the pre-covid days, I don't think it'd be socially acceptable to talk to someone within a foot of their head).
I'm not saying cloth masks don't help at all, just that they help very, very little. Consider that the filtration efficiency drops from the numbers in that table immediately after you start wearing it, and that it gets reduced a further 1-4x after you've washed it the first time[2], it's not really worth the effort, hence WHO discourages it.
[1]https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2843952/
[2]https://www.koreascience.or.kr/article/JAKO201521839156288.p...
The first paper you linked to does not look at respiratory droplet transmission with a mask on.
The second paper only has the abstract in English. I can't read Korean, but based on the abstract they're looking at pressure drops across a cloth filter.
Again, it's not about direct filtration. It's about disrupting the stream of viral particles from one person's airway directly into another person's airway.
I'm 100% open to criticism on why my model doesn't make sense, but my foundational premise is that masks function primarily by disrupting direct stream of viral particles from one person's airway to another primarily when facing each other and vocalizing.
This paper shows the change in dispersion of respiratory droplets when placing a surgical mask on a coughing patient (surgical mask being very similar to the cloth masks people are using).
Exhaled Air Dispersion during Coughing with and without Wearing a Surgical or N95 Mask
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3516468/
"During normal cough, exhaled air dispersion distances along the median sagittal plane was significantly reduced to ≤ 30 cm when the HPS wore either a surgical mask or a N95 mask."
Figure 3. really shows this in a graphical form.
Here's another cool paper.
Textile Masks and Surface Covers—A Spray Simulation Method and a “Universal Droplet Reduction Model” Against Respiratory Pandemics
https://www.frontiersin.org/articles/10.3389/fmed.2020.00260...
"Using a bacterial-suspension spray simulation model of droplet ejection (mimicking a sneeze), we quantified the extent by which widely available clothing fabrics reduce the dispersion of droplets onto surfaces within 1.8 m, the minimum distance recommended for COVID-19 “social distancing.” All textiles reduced the number of droplets reaching surfaces, restricting their dispersion to <30 cm, when used as single layers."
I have a box of 100 CDC tested KN95 I've been giving out. They failed testing for medical use by 2% (93 instead of 95% of particles blocked), so they aren't reserved for medical workers but they're damn close to as good
Virus mutations are not rare events. This is what supports the natural evolution/selection/mutation of a wild virus into Sar-cov-2 hypothesis. People often say that the "natural hypothesis" is far more likely than a virus escaping a BSL4 lab. Let's look at that.
According to Wikipedia, there have been 3 virus outbreaks in "wet markets" in the last 20 years (https://en.wikipedia.org/wiki/Wet_market#Health_concerns). That makes about 1 outbreak in 7 years.
That's for China as a whole. China is big. The probability of having a virus outbreak in a particular town is of course somewhat lower. The particular town we are looking at is Wuhan: this is the only city in China having a BSL4 lab, and it did gain of function experiments on Coronaviruses.
There are 108 towns with more than 1m population (https://all-populations.com/en/cn/list-of-cities-in-china-by...). We're going to make rough estimates: let's say there are 100 "wet markets" in China, about one per city >1m. That makes the probability for a natural virus outbreak in _a_given_ "wet market" to be 1 in 700 years.
The question to be answered is this one: what is the most likely event between:
1/ a natural virus outbreak at Wuhan's "wet market"
2/ a modified virus "escaping" Wuhan's BSL4 lab
Hypothesis 1 has been estimated at 1 in 700 years. Do you believe the probability of hypothesis 2/ to be much lower than 1/?
Would the probability of hypothesis 1/ be 1 in 100 years, would you still thing it is much bigger than hypothesis 2/?
If it was deliberate why release it in China why not somewhere else? If it had to be in China for some magical reason then why not test on say the Uighurs?
Also add in things like Ebola and Hiv probably being linked to bushmeat (https://en.wikipedia.org/wiki/Bushmeat), Small pox, the bubonic plague plus a bunch of others from rodents.
Outside of better evidence the "escape" theory belongs to B-Grade Netflix movies and conspiracy websites.
After September 11, the next immediate terrorist attack on US soil was the anthrax scare. It was likely initiated by a specific researcher who had relevant access to the lab and had been lodging complaints for years that US authorities weren't taking anthrax threats seriously.
(The scientist in question never faced justice because they committed suicide before the dragnet closed in on them --- https://en.wikipedia.org/wiki/2001_anthrax_attacks).
Or just a natural one. The virus doesn't need to have been engineered/synthesized/mofidied for the Wuhan lab to accidentally/purposefully released it (for the record, if it did originate from the lab I would bet it was accidental).
Don't forget that the Wuhan lab was also part of a US government funded program to help prevent future pandemics[0]. So the lab likely handled natural viruses. The program's funding was cut/stopped last year & an article about it was posted on HN (flagged & removed). I quoted + commented on the HN posting/article back then[1]. Here is the snippet I previously quoted:
> Two months before the novel coronavirus is thought to have begun its deadly advance in Wuhan, China, the Trump administration ended a $200-million pandemic early-warning program aimed at training scientists in China and other countries to detect and respond to such a threat.
> The project, launched ... in 2009, identified 1,200 different viruses that had the potential to erupt into pandemics, including more than 160 novel coronaviruses. The initiative, called PREDICT, also trained and supported staff in 60 foreign laboratories — including the Wuhan lab that identified SARS-CoV-2, the new coronavirus that causes COVID-19.
> Field work ceased when the funding ran out in September
The Wuhan lab was also first to identify & sequence SARS-CoV-2[2]. Coincidence or not, that part makes sense either way because it's a BSL4 lab & it's located in the same city as the first cases.
[0] https://www.latimes.com/science/story/2020-04-02/coronavirus...
[1] https://news.ycombinator.com/item?id=22766157
[2] https://virological.org/t/novel-2019-coronavirus-genome/319
Improbable things sometimes happen. Improbable things sometimes happen before a more probable thing happens.
My physician father was involved with a case where a drunken idiot decided to go play on a beach filled with elephant seals. The deep tusk wound he earned in one thigh had the local internists hitting the books to figure out what rare and exotic marine bugs had infected the fellow... IIRC the guy lived, but he was very ill.
Sometimes I wonder if he lives on in textbook case studies (with the requisite black bars over his eyes in any photos).
Threadreaderapp is silly.
Shifting our food sources away from industrial animal agriculture would significantly decrease the number of new infectious diseases we have to encounter. This looks like lab grown meat, like plant based meat substitutes such as Impossible, Beyond, and Oatly, like grass fed beef, like backyard chickens, and it looks like less beef burritos and more bean burritos.
Two separate papers have come out saying pretty much the same thing, that there is lots of evidence pointing to this virus being more likely engineered (by modifying existing viruses) and that each piece of evidence also matches papers put out by researchers working at the Wuhan-based virus research lab, which is also where the outbreak is thought to have begun.