New coronavirus losing potency, top Italian doctor says | Hacker News Reader

New coronavirus losing potency, top Italian doctor says

reuters.com

50 pointsadventured66 comments

Coronavirus have “proofreading” functions that make them less likely to mutate meaningfully than many other kinds of viruses.

While it’s true that viruses often mutate to become less potent over time (bc that makes them less detectable and therefore more likely to spread, an evolutionary advantage), any claims that this is happening should require very strong evidence to be believed. This isn’t even weak evidence.

Most of the above is googleable. I don’t have direct citations because most of my understanding comes from the excellent This Week in Virology podcast where various virologists chat about such issues. They’re quite dismissive of the frequent “The virus is mutating” stories (though of course all viruses mutate in small, unimportant ways all the time)

It sounds to me like the doctor is anthropomorphizing the virus and saying what the people want to hear. It may be that the pandemic is receding for a variety of reasons, but that's almost certainly not because the virus itself has mutated.

He actually said he's aware there are no known mutations that can be traced to a different clinical phenotype (Reuters did not report that part).

Reuters touched only briefly what Dr.Zangrillo said. He is aware there are no mutations that could be traced to any change in clinical outcome (everyone else who talks about "reduced potency" also acknowledges that fact).

But indeed, lockdowns or not, there has been a decrease in ICU usage and in viral load of patients. Treatments have also improved somehow (aside the "ventilator yes or no" debacle, according to Dr.Gattinoni, an Italian doctor working in Germany, the actual intubation parameters like flow of oxygen, etc. have also changed).

People think social distancing and masks may have played a role (probably), but bear in mind that until the beginning of May, the government was still saying that masks were useless (a thesis still shared by some Italian experts). Only Lombardia mandated them also outside (as far as I remember).

Personally (I don't have any evidence to back it up so far, so it's just speculation), I think that the route of infection matters. The vast majority of cases in the past two months were in nursing care homes (a complete screening in Lombardia in the past days found 30% positives there) and in hospitals, which also mean more viral load (closed systems) and more vulnerable people.

That is no longer the case now. I know that some doctors are now handling people in "house confinement" rather than bringing them to the hospitals.

P.S.: Testing capacity indeed increased but there's a lot more to do to get to decent levels.

I am suprised who weak doctors are in Math! You don't need to be a Math genius to grasp this: initially, they were testing symptomatic people, mostly people with high fever, and we know not all develop fever. So, now, testing has opened up to more people, i.e. asymptomatic and with mild symptoms. It's beyond obvious that CFR will drop! CFR will always drop with time - unless the virus mutates and becomes more severe. Also, many dilute the mortality with some unreliable antibody tests, which also are not randomized samples. In the Balkans, the antibody tests show very low infection rate, yet, the epidemic has effectively stopped - more than 2 weeks after the restrictions got removed. Obviously, the Summer weather is helping, but this also means that, for sure, there will be a second wave in the Fall as infections are still growing and in some areas they are literally just in the beginning.

I think it's also for evolutionary reasons. A virus that is milder survives better and spreads more. A virus that kills the host, or in this case makes it sick so that it self-isolates, has lower fitness.

The so-called Spanish flu pandemic (not Spanish at all, probably from Asia as well) went this route. It became very mild and the pandemic vanished quickly after killing millions.

https://en.wikipedia.org/wiki/Spanish_flu#Deadly_second_wave

https://www.telegraph.co.uk/news/2020/05/31/second-wave-coro...

Posting only links or references can leave it unclear if you are agreeing, disagreeing, clarifying, or what.

Does it matter? As long as the information is factual, it is useful. Not every comment must take some side in some imagined argument or debate.

With its long incubation period and asymptomatic spreading, I don't see how sars-cov2 would benefit by becoming weaker.bthwre is little evolutionary pressure for it

The weaker the virus, the less symptoms it has. If people who feel sick stay home, it gives less aggressive stains the chance to infect more people.

On the other hand if infected people with strong symptoms infect others in hospitals, the opposit happens (that's how the Spanish flu first got more deadly).

HIV, Lassa virus, and Ebola hasn’t mutated in something milder. If anything, NextStrain has shown that the mutation rate for SARS-CoV2 is about 5x slower than seasonal influenza.

This is a possibility, but we need hard evidence before we can say it is happening with the current coronavirus.

There was some report quite a while ago from Singapore that they saw deletion variants with lower potency iirc.

As the global diagnoses go up, the daily death rate is declining, so this makes sense.

Variables changed; social distancing is in effect, medical field is much more effective then it was two month ago. But hey lets say magically virus is changed.

In what way it makes sense to you ?

Viruses mutate. There is a selection pressure for them to become more contagious but less incapacitating since sick people in bed do not infect others. It is possible, though not guaranteed that common strains of COVID could become less deadly over time. That said, public health decisions should be based on the science and not wishful thinking or what one doctor said.

Scientists use data from here: https://nextstrain.org/ to make such claim, to best of my understanding, there no-such claim.

The directed evolution of a virus, as mentioned, to become more invective but less lethal can be explained by game theory and is backed up by experience. But is is not a law, could also go otherwise around.

I do not dispute such possibilities, there is also possibility it will mutate into flying AIDS. The process is about complex systems interactions and claim that it is attributed slowly to virus mutation without such evidence is outright reckless, unprofessional, and unscientific.

I don't care what you dispute or not. It is unlikely that you are qualified to make any statements about this or that you have ever worked in genetics on a high level.

It is Biology 101:

https://en.wikipedia.org/wiki/Optimal_virulence

Not sure if you have enough cognitive abilities to understand this:

https://en.wikipedia.org/wiki/Ad_hominem

You just made a statement about a field of science where you seem to have zero educational background and understanding and described something as "without such evidence is outright reckless, unprofessional, and unscientific" and I called you out on it with some Biology 101 information with a Wiki Link. Where is your problem?

My fist problem is that; you did not refute what I stated, but instead choice to attack my experience. While I am not medically trained, I studied genetic optimization extensively, most importantly phenotypes effective behavior within individual phenotype cells; functions, locations, and connections.

My second problem is that; you linked article without any explanation how my statement is false in relation to linked article.

My third problem is that; I just don't understand what in my statement is so false that grants attacking my experience, in simple analogy; in case 5 years old tells you 2+2=4, clearly his age is irrelevant for what he is saying to be true.

Finally, I explain what I said in original statement; if you have x, y, z variables claiming without evidence that x is only responsible for output value, and without providing evidence why y and z is not responsible is reckless, unprofessional, and unscientific in another words it is just speculation. Note that article ended with “It is clear that today the COVID-19 disease is different.”

Please do not do personal attack or flamewar on HN.

https://news.ycombinator.com/newsguidelines.html

You are of course correct that this possible or even likely, but we can't say it is already happening without hard evidence.

Please don't cross into personal attack or flamewar on Hacker News.

https://news.ycombinator.com/newsguidelines.html

You're completely right, but just to highlight that it's "not guaranteed," the 1918 flu started out fairly mild and then mutated into a much deadlier strain.

(I'm reading John Barry's The Great Influenza right now.)

Who said anything about magic?

In my perspective it is literally binary decision; use scientific statement to explain phenomena or magic.

Clearly you aren't a frontend dev.

I am not sure what this has to do with topic discussed at hand, but I guess I am not, only frontend I developed was equities market Level II data window with support for hotkeys and algorithmic trading.

It's a joke about science and magic.

oh, I just did not connected with a joke. We had situation where packets dropped magically, for two weeks it was very stressful situation to say the least, because ~10 people could not pin point where it was happening. It was not magic it was a fucking L2 switch in a server room, that I broke to tiny pieces, yelled at boss: "we need more expensive equipment". End story no one questioned equipment cost thereafter.

I tend to think of "magic" as having the connotation of something working for no obvious reason, not something breaking for no obvious reason.

Which is what happens when "something working for no obvious reason" breaks.

According to Google Translate, in Italian, "potenza" means strength, ..., potency

I wonder if the doctors in the article used this word to describe the loss of potency, but the media and translators are equivocating this to mean "strength" (which is a more intrinsic quality, and suggests a mutation).

My first guess was that because summer is starting, people are getting more Vitamin D, and this is making the virus less effective. Alternatively (as others have stated in this topic), the virus could mutate to spread more effectively but lose its strength on individual people, and this would still be considered an evolutionary advantage.

As testing becomes more readily available, we'll catch more and more people who are asymptomatic and/or have mild cases. This is going to reduce the CFR. Many epidemiologists predicted this and have stated that they think the IFR could be as much as an order of magnitude lower than what the CFRs were back in March.

nextstrain.org disagrees.

There doesn't seem to be any significant mutational difference between the Italian virus clades than anywhere else.

Says one doctor.

Well, Italian doctors, for some, have higher credibility! :D

News is only to be taken serious if it’s from the experts that agree with my point of view.

No, says science, experience and game theory. While this outcome is not guaranteed, it is basically expected.

>The strength the virus had two months ago is not the same strength it has today

If the virus had not mutated maybe it's that people have got some kind of immunity through low level eposure?

Could this be due to mutations?

Mutating to survive less successfully in your environment would be evolutionarily unusual...

Success in this case is spreading to more people. Mutating to cause less severe symptoms + be more contagious is evolutionary the way these things go.

Thanks - yeah, I guess that does make sense.

Sure, for less and declining viral loads. But this is mostly anecdotal.

This is not science, this is magic right there.

“It is clear that today the COVID-19 disease is different.” The only difference is social distancing, for fucks sake.

Citation needed.

I am not sure what you asking for, my point is; if you make extraordinary claim that virus mutated without evidence then it is magic. Even if there evidence of mutation that make virus less potent; you still have to make clear link how it is not result of changed variables such as, but not limited to; social distancing and medical stuff effectiveness.

I think we’ve mostly advanced past the point of view that mutations are magic, it’s well known they happen. That’s hardly an extraordinary claim.

Mutation is not a magic, in fact neat in my nick name stands for Neuro Evolutionary Augmented Topologies. Point is, you have to demonstrate concisely location of mutation with effects of less potency in addition to effects of changed environmental variables.

Not exactly, there was a series of articles from a virologist here on HN (cant find it), the idea is that he wanted to infect people with the less deadly corona versions so we all gain immunity. This would prevent a lot of casualities. This idea also works the same way in nature, as in the less deadly virus can spread more, because it produces milder symptoms and even no symptoms. This means you are more likely to catch a milder version, which leads to the fact that the virus becomes less dangerous, as deadlier strains will fade out quicker. This does not mean we need to let go the social distancing at all, but on the other hand we have to reach herdimmunity at some point, preferrably without too much casualities.

I re-read the article and might be mad, but this is your interpretation or rationalization of what doctor said.

I wrote down the reason why the virus is “getting” weaker. There is no explanation of the phenomena in the article, the doctor just talks about what he experiences without an explanation. Social distancing alone wouldn’t help us, we also need the herd immunity, otherwise the virus would just flare up randomly the second we ease the restrictions. The mechanism I mentioned helps us to achieve herd immunity with time. I don’t understand why is that getting downvoted... Meanwhile I found the article: https://www.tillett.info/2020/04/05/a-solution-to-covid-19/

(found it) Link:

https://news.ycombinator.com/item?id=22810639

Clearly not true. For example, mask wearing is another difference in many places.

This was my mistake not outlining all the differences (technically it is social distancing), another one would be medical stuff is much more effective in treatment, and another one would be diagnoses are increased orders of magnitude.

It could be the proportion of iatrogenic deaths is decreasing. Like, initially hospitals were being aggressive with ventilators on people who were very ill, because "what do you have to lose", and then there were some articles about being more judicious in their use and cutting mortality substantially.

Weather too.

In what way weather effects virus spread is beyond my understanding.

various possible ways: for instance (theoretically) heat and humidity might effect how long virus survives intact outside of the host, or increased UV light exposure could speed up virus breakdown.

UV light makes sense, humidity and heat does not, because if I am not mistaken; in summer humidity can be substantially higher then in winter and body temperature is fairly high compered to outside average.

Consider that just raising the internal body temperature by a few degrees is a major mechanic in your immune system. Many diseases are not tuned for 100 degrees Fahrenheit

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