I am not a Doctor but I play one on DU...

[kentuck]

Why does the virus affect people in such varying degrees?

Some people get a little sick (a touch of the flu) and some people get deathly ill and die? Why is that? Is it their individual immune systems or is it something else?

It seems to be most deadly when it gets into people's lungs. It destroys their ability to breathe.

Is it possible that it can get into the body from at least two places, thru the nose and thru the mouth?

If it is on food or is digested internally in some way, it would maybe have a different effect than if breathed directly into the lungs?

To repeat, I am no Doctor, but just a thought.

[California_Republic]

1. Good question

I was hoping there was good follow up research. Such as when a 30 year old dies then maybe they were a vaper, smoker, or other info that would be a clues.

[madaboutharry]

2. I don't know the answer to this of course,

but it is that way with other diseases too. There were people who contracted Polio who ended up dying or in an iron lung and others who recovered completely. Life is so precarious and sometimes we never know the answer to why someone lives and someone dies.

[kentuck]

3. From what little we do know...

...it would seem very important that more of us should be wearing masks.

[marble falls]

9. The common wisdom seems to be that masks work better by putting them on the sick ...

that they don't do much for the healthy.

[GreenPartyVoter]

26. Depends on whether or not it makes it harder for them to breathe when they're already struggling.

[Bev54]

29. Masks will not protect us

The medical masks that are fitted to their face, will help medical staff but not the ones we get. The masks should only be worn by those who are sick or think they may be to stop droplets being coughed or sneezed out into the air.

[RobinA]

30. Polio

is exactly what I was thinking of when I read the OP. I had read some time ago that they believe most people had had polio (prevaccine), but only some got problematically sick. My uncle, the youngest of two kids, my mother being the oldest, got a major case while nobody else in the family got sick. My father, who lived to be 83, was a physician and I never knew him to be sick a day in his life, and he smoked a fair amount. Some people seem to get things and some people don't.

[former9thward]

4. You can say that about any disease.

Some people get a touch of the flu. Hardly sick at all. Some people die from it. Depends on immune system strength, how much of the virus you got, underlying body strength, your genetics, age, and probably a hundred other factors we don't know about.

[kentuck]

6. So, how is this one any different ?

Other than the unknown and the fact that there is no vaccine.

[nycbos]

7. From my albeit limited understanding...

... it spreads much faster. People can infect others before they even have systems.

[jberryhill]

15. Because....

1. The incubation period seems long, and as a result there are a lot of asymptomatic people who are shedding the virus before developing any symptoms itself.

2. The probability of infection as a consequence of any particular contact event appears high.

3. The probability of serious complications appears higher than other viruses.

4. Because it is novel, human immune systems don't have tens of thousands of years of accumulated immunity.

Why did Native Americans die in vast proportions to diseases that were common among Europeans? The answer is that Europeans had been tending livestock unknown in North America for many generations, and had shared viral materials with pigs, goats, sheep and cows with which they lived in tight quarters for many hundreds of years.

[imavoter]

17. It's new. "novel"

Humans have no natural immunity
to this because our bodies have never encountered it before.

There's not really much evidence why it affects some more than others.
It's only been known about for a few months, so not a ton of research yet.

[Beringia]

35. A 36 year-old died from it and she looks very strong

A Brooklyn principal has died due to complications of the coronavirus, the first known death of a New York City public school staff member connected to the epidemic, city officials confirmed Monday evening.

The principal, Dez-Ann Romain, ran Brownsville’s Brooklyn Democracy Academy, a transfer school that serves students who have struggled at traditional high schools and are unlikely to graduate on time.

Romain was 36, according to public records and an education department superintendent.







https://chalkbeat.org/posts/ny/2020/03/23/a-brooklyn-principal-has-died-from-coronavirus-complications-principals-union-says/

[former9thward]

37. We have no idea what her medical history has been.

No idea.

[catrose]

5. My qualifications: long-time cat rescuer

Coronaviruses are rampant in cat colonies, including multicat households, so much so that there’s no point in testing for it. But in a small number of cases, it activates into Feline Infectious Peritonitis, with close to 100% mortality.

No one really knows how and why it activates. My observation tells me it’s more likely to be in a kitten who’s been very ill—but that kitten could have 6 siblings who survive and never show symptoms.

[Freddie]

25. My beloved Freddie died of FIP

Vet said most cats have been exposed to the virus but it mainly kills very young kittens and cats over 10 (Freddie was 10).

[catrose]

31. I'm so sorry. It's such a cruel disease.

I hope with all the research on this virus that we'll learn something about coronoviruses that will benefit cats too.

[getagrip_already]

8. not a doctor either, but...

I heard a discussion from some scientists who were talking about viral loading and inoculate levels. Viral loading is the amount of active virus units in your bloodstream and inoculate levels are the amount of virus you are exposed to at once.

What they were saying is that the higher the dose of inoculate you receive, the faster and higher your blood builds up a viral load.

They said that in other diseases, it is known that a higher inoculate will result in a faster and more serious onset of disease. For example, if you receive a direct sneeze or cough at close distance you will very quickly get sick and more so than someone who only received a small dose.

They said that is because the lower the initial dose, the longer it takes to multiply in your system and the more time your immune system has to identify and deal with it.

This was in the context of why even paper face masks are a good idea for healthy people to wear. If you can reduce the amount of virus you ingest, you run a much better chance of having a milder form of the disease.

So why does the CDC say it doesn't protect you? First, they simply don't have enough masks. They are short by tens of millions and they have known this since december. Second; trump is an idiot and he doesn't like the look of a country running around in face nasks - it would send the wrong message and hurt his image. Third - they are technically correct - a simple face mask won't provide the absolute protection an n95 mask would, but that is not the question.

You decide. I'm not an expert but this sounds reasonable to me.

[kentuck]

10. Interesting.

Thanks!

[Hugin]

14. Thanks for clarifying a couple of terms for me, getagrip.

'Viral loading' and 'inoculate levels'...

I suppose reducing the 'inoculate levels' is the whole point of the social distancing.

By the time you're worried about 'viral loading' the patient is already in trouble.

[former9thward]

19. Your last paragragh is dead wrong.

Your slander against the CDC is very misleading. The CDC says masks are not needed for healthy people because masks do not protect against the virus. If you can breathe through the mask then the virus can get through also. A mask is useful if you are sick because if you sneeze you will not be putting droplets out in the air and on surfaces. For healthy people to be wearing masks just means than health care people have less access to them.

[getagrip_already]

24. not at all wrong - and I acknowledged their statement...

They say it doesn't protect you against the virus which is true. I said that. But what masks do is reduce the inoculate level you would be exposed to without one, and therefore still a benefit.

The CDC is a far cry from what it was 4 years ago. It is a political arm of the government with a few vestigial scientists too afraid to say what they think. Much like NOAA.

So I'm not saying you are wrong, but neither am I.

Masks DO NOT protect you from the virus, but they can help you get a lower dose of the virus. N95 masks do protect you, at least from breathing in the virus. Your eyes or cuts are another matter.

[Beringia]

36. This is what I have heard too

A regular face mask will reduce the inoculate amount.

So even if you ruin someone else's mellow by seeing you wearing a mask, it can help protect you.

[Ms. Toad]

34. There is a difference between not needed - and not useful.

And a fallacy in your statement:

If you can breathe through the mask then the virus can get through also.

ALL masks can be breathed through. If not, all of our doctors and nurses would have died of asphyxiation.

It is true that it is more difficult to breathe through N95 masks (with 3 micron openings) because the openings are small enough to prevent passage of the covid virus (1 micron) attached to anything up to 3 microns across. The openings in other masks are larger and do permit passage of larger particles.

So other masks stop less, but they are still helpful - especially against droplets (significantly larger than 3 microns). To the extent the droplets contain a high viral load, the protection may be significant.

And, the CDC finds them useful even in medical settings - they are authorizing them when nothing else is available:

HCP use of homemade masks:
In settings where facemasks are not available, HCP might use homemade masks (e.g., bandana, scarf) for care of patients with COVID-19 as a last resort. However, homemade masks are not considered PPE, since their capability to protect HCP is unknown. Caution should be exercised when considering this option. Homemade masks should ideally be used in combination with a face shield that covers the entire front (that extends to the chin or below) and sides of the face.

https://www.cdc.gov/coronavirus/2019-ncov/hcp/ppe-strategy/face-masks.html

If health care professionals (HCP) are allowed to use them when PPE is not available, the CDC obviously considers them to be of some value (and tests have shown they do halt a significant portion of the virus)

So the poster is correct that the restriction is largely because it is MORE critical that HCP have access to face masks because they are more at risk.

[yonder]

28. Good, easy to follow post.

[Hugin]

11. There are so many variables...

Underlying conditions, viral loading, and on and on.

Predicting a prognosis is virtually impossible.

I suppose that's why it's called 'practicing' medicine rather than 'doing' medicine.

It's best to not get it in the first place.

[jberryhill]

12. Why do some people win jackpots in Las Vegas slot machines and other people don't

"Some people get a little sick (a touch of the flu) and some people get deathly ill and die? Why is that? Is it their individual immune systems or is it something else?"

Nature adores probability distributions that usually look like this:



Flip a coin 100 times, and tote up the number of "heads". Then go ahead and do that 100 times flipping experiment 1000 times.

Now, plot the number of times that you got, say, 45 heads, 46 heads, 47 heads... and so on.

You are going to get a curve that looks a lot like that one up there ^^^^.

Nothing in complex systems follows rigid rules, but outcomes are usually centered around a mean.

Any disease in any population is going to have a range of outcomes.

If you pushed people down stairs and had an "index of bad results" that measured anything from "just fine" to "10 broken bones" to "dead", then you'd get a similarly shaped curve. It's simply the way things are when you are dealing with an event over a large number of instances - the outcomes will arrange themselves in accordance with one or another probability distribution (and there are common probability distributions that look different from the one pictured above, but the Gaussian is the most familiar).

[kentuck]

13. Assuming all diseases were equal...

...that would make sense.

[jberryhill]

16. What do you mean by equal?

The things that differ in various probability distributions are how narrow and high, versus short and squat, the curve is.

Anything has a median outcome - i.e. what happens most of the time - and outliers on on either side - i.e. what happens some of the time.

An infection from a paper cut can kill you. Most of the time, it won't, but once in a while, yeah.

[kentuck]

18. The odds that you will die from a paper cut is much less than coronavirus...

...so I think we would have to look at the probabilities from an individual perspective.

[jberryhill]

20. I'm sorry you don't get it

I'm going to guess that you didn't take a whole lot of mathematics.

Math is fundamental to everything. What I'm talking about is the SHAPE of a normal probability distribution. If you plotted "how long does it take for a paper cut to heal", you'd get a very narrow curve.

For a paper cut, you get a range from "no infection", to "mild infection", to "severe infection", to "fatal infection". The absolute numbers aren't important.

Take a look at this, for example:



Take a look at the red line for China.

Okay, now, here are a bunch of normal distribution curves (from the wikipedia entry):



Now, on a normal distribution, if you add up the area under the curve, the "cumulative probability graph" looks like this, for each of those colored lines in the picture above:




Finally, compare those cumulative probability distribution curves to the cumulative fatalities red "China" curve in the graph above. Do you notice something?

Do you see how the cumulative China fatalities looks like the light brownish cumulative normal probability curve?

Every country is going to have a curve that looks the same. The only question is how high and narrow it will be, or how wide and flat it will be. That is the entire point of the "flatten the curve" thing you've been hearing.

Mathematics describes things in a general case. The only differences are the individual parameters of a particular set of statistics governing whatever phenomenon one is looking at. That's why science uses mathematics to model the physical world - even diseases.

[kentuck]

21. General math is about as far as I got.

You are right.

[jberryhill]

22. Not a problem

If everybody did the same thing, we'd never get everything done that needs doing.

But, at the end of the day, the basic answer to the question of "why are outcomes different" is due in large part to why some people win the lottery and other people don't. It's simply probability.

[jberryhill]

32. Here, I posted an OP for you

You might find this interesting:

https://www.democraticunderground.com/100213166756

[Ligyron]

27. Really excellent, clear and concise explanation complete with graphs.

That Stat 5 something, something level course in college was pretty difficult for most students and they should have required more math prerequisites for it ... which they did. Eventually.

[jberryhill]

33. Here, try this

https://www.democraticunderground.com/100213166756

[Mariana]

23. My friend's son woke up with a mild sore throat one morning.

By suppertime, he was in the hospital in very serious condition.

It was ordinary strep A. For some reason, rather than just giving him a sore throat, the strep infection ran rampant in his whole body, including his lungs and his brain, and it almost killed him. Why did that happen to him? No one knows.