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How many microbes does it take to make you sick?

quantamagazine.org

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Re: How many microbes does it take to make you sick?

#61

Post by zby »

If 400 microbes that contact your body makes you sick - then what if one virus gets into a cell and produces 400 copies? It is certainly possible: "For example, SIV, a cousin and model for the HIV virus, is released from infected T cells with a burst size of ≈50,000 (BNID 102377) whereas cyanobacterial viruses have characteristic burst sizes of ≈40-80" http://book.bionumbers.org/how-many-virions-result-from-a-si... So if not just one - then a few initial virions should be able to produce the infectious dose.

I guess time is important here - the organism detects the initial virions and prepares defences - so if the infectious dose amount of virions comes after the organism is warned they fail to grow into an infection. But my intuition is that the complexity of that process and path dependence makes that infectious dose so variable - that it does not seem to be any useful.

Re: How many microbes does it take to make you sick?

#62

Post by sfblah »

sokoloff wrote: post #57
AnthonBerg wrote: post #42

Earlier quoted context omitted.

The un-cited Cochrane review in question does not say that. From Cochrane.org: Statement on 'Physical interventions to interrupt or reduce ... - Cochrane Mar 10, 2023 Many commentators have claimed that a recently-updated Cochrane Review shows that 'masks don't work', which is an inaccurate and misleading interpretation. It would be accurate to say that the review examined whether interventions to promote mask wearin…

It looks like FFP3 are analogous to N99 masks. A mask mandate that permits "wrap a piece of T-shirt over your mouth, some of the time, sometimes even covering your nose" (which is not far from what I saw for much of 2020) is, unsurprisingly, going to be more effective at ensuring grudging compliance with a mandate than it is to reduce the spread of an airborne virus.

This is the problem with mask absolutists. They take data from masks that are super effective (hospital setting, correct usage, basically gluing the mask to your face) and extrapolate it to some guy on the subway with a cloth mask. It’s a bad way to make public policy, and I don’t really understand the motivation behind it.

Re: How many microbes does it take to make you sick?

#63

Post by sfblah »

AnthonBerg wrote: post #42
sfblah wrote: post #16

Earlier quoted context omitted.

What you said isn’t controversial. It’s definitely right. The issue with masks is one side started treating them like a talisman that makes infection impossible, which provoked the other side to say they do nothing. On a population level, masks are probably close to ineffective against a viral pathogen. You can read the relevant Cochrane review to see that. On an individual level they obviously do something, but you…

The un-cited Cochrane review in question does not say that. From Cochrane.org: Statement on 'Physical interventions to interrupt or reduce ... - Cochrane Mar 10, 2023 Many commentators have claimed that a recently-updated Cochrane Review shows that 'masks don't work', which is an inaccurate and misleading interpretation. It would be accurate to say that the review examined whether interventions to promote mask wearin…

I would encourage readers to read the “Main results” section of the review for themselves. It takes under 5 minutes. Don’t trust a commenter on any online forum on this topic (myself included), as it’s completely politicized.

Re: How many microbes does it take to make you sick?

#64

Post by maxerickson »

sfblah wrote: post #59
maxerickson wrote: post #52

Earlier quoted context omitted.

which provoked the other side to say they do nothing. This somewhat excuses their reactionary stupidity. Like they weren't "provoked", the use of masks wasn't directed at them.

Where I live, in Alameda County, California, masks were required outdoors if you were within 30 feet of another person. This ridiculous policy lasted about a year and provoked all kinds of altercations. It also made exercise, a key way to say fit, much more difficult. So, in this case I would argue mask use was in fact “directed at” people.

When you say that, you are saying that the policy was put in place in bad faith in order to inconvenience the people that didn't like it. The argument is more ridiculous than the policy.

Here there was never an outdoor mask policy, so I didn't ever have a chance to evaluate my reaction to such a thing. There was apparently a policy banning stores like Walmart from selling seeds (which I interpreted as bureaucratic friction rather than intention, something that was born out relatively quickly in practice, and never in the minds of the reactionaries).

Re: How many microbes does it take to make you sick?

#65

Post by dorfsmay »

jameshart wrote: post #11
dorfsmay wrote: post #8

Earlier quoted context omitted.

> boosting ourantibody response What I wonder is if we can develop immunity (not boosting, assuming never been infected before) from being exposed to small doses, or do we need at least one full blown infection.

Not sure why you are suggesting the basic mechanism of inoculation, which has been known for centuries and is the fundamental mechanism behind vaccination, as if it’s a novel hypothesis. Have I misunderstood what you’re getting at?

Dosage. Vaccines use deactivated viruses, but I don't think they use "tiny amount".

Re: How many microbes does it take to make you sick?

#66

Post by sfblah »

maxerickson wrote: post #64
sfblah wrote: post #59

Earlier quoted context omitted.

Where I live, in Alameda County, California, masks were required outdoors if you were within 30 feet of another person. This ridiculous policy lasted about a year and provoked all kinds of altercations. It also made exercise, a key way to say fit, much more difficult. So, in this case I would argue mask use was in fact “directed at” people.

When you say that, you are saying that the policy was put in place in bad faith in order to inconvenience the people that didn't like it. The argument is more ridiculous than the policy. Here there was never an outdoor mask policy, so I didn't ever have a chance to evaluate my reaction to such a thing. There was apparently a policy banning stores like Walmart from selling seeds (which I interpreted as bureaucratic fr…

There’s a fine line between a policy being intended to harm and just being stupid. Regardless of the rationale, I was just trying to demonstrate how such policies were in fact weaponized.

You can do some reading about the Bay Area and debates over whether government policies are in bad faith. I think it’s at least arguable that some are in fact in bad faith (meaning, no one really thinks they’ll serve any public purpose other than punishing groups of people).

Re: How many microbes does it take to make you sick?

#67

Post by dorfsmay »

yieldcrv wrote: post #58
vikramkr wrote: post #14

Earlier quoted context omitted.

Yep that's called vaccination! No need to get a full blown infection it's how we eradicated smallpox

I’ve gotten lots of anti vaxxers to be into vaccines by saying what the parent said, most of them are just allergic to the word vaccine and don’t know what it means, (specifically I’m referring to using dead pathogens not just a low dosage of live ones) so just describe the procedure, and call it a secret that big pharma doesnt want them to know, and theyre into it. be anybody but a doctor lol slam dunk

I'm not anti vaccine, no need to out words in my mouth.

My understanding of vaccine is that they use deactivated viruses but not small doses.

My question is about live viruses, and if we can get exposed to small doses enough that will trigger a immunization mechanism without triggering a full blown infection? Or does it work to boost an existing immunity only.

Re: How many microbes does it take to make you sick?

#68

Post by [deleted] »

yieldcrv wrote: post #58
vikramkr wrote: post #14

Earlier quoted context omitted.

Yep that's called vaccination! No need to get a full blown infection it's how we eradicated smallpox

I’ve gotten lots of anti vaxxers to be into vaccines by saying what the parent said, most of them are just allergic to the word vaccine and don’t know what it means, (specifically I’m referring to using dead pathogens not just a low dosage of live ones) so just describe the procedure, and call it a secret that big pharma doesnt want them to know, and theyre into it. be anybody but a doctor lol slam dunk

[deleted]

Re: How many microbes does it take to make you sick?

#69

Post by api »

dorfsmay wrote: post #67
yieldcrv wrote: post #58

Earlier quoted context omitted.

I’ve gotten lots of anti vaxxers to be into vaccines by saying what the parent said, most of them are just allergic to the word vaccine and don’t know what it means, (specifically I’m referring to using dead pathogens not just a low dosage of live ones) so just describe the procedure, and call it a secret that big pharma doesnt want them to know, and theyre into it. be anybody but a doctor lol slam dunk

I'm not anti vaccine, no need to out words in my mouth. My understanding of vaccine is that they use deactivated viruses but not small doses. My question is about live viruses, and if we can get exposed to small doses enough that will trigger a immunization mechanism without triggering a full blown infection? Or does it work to boost an existing immunity only.

There are many different kinds of vaccines that work in slightly different ways. “Vaccine” is a class of treatments akin to “anesthetic” or “antibiotic.”

Some are weakened live agent. Some are killed or neutralized agent. Some are just a protein or other piece of the pathogen. Some like mRNA vaccines are code from the pathogen that causes your body to generate and then sensitize against something. There are probably other types.

I do find the oversimplification in the debate frustrating. Either all vaccines are bad or all vaccines are great when in reality each one is a different thing. As with other drugs some work better than others and some have side effects while others mostly do not.

As near as I can tell the mRNA COVID vaccine is fairly effective at reducing severity and duration of infection but not nearly so at completely preventing infection. There is a small risk of side effects but the danger from a more severe COVID infection is statistically much greater.

Creating a vaccine in a year is nuts. What we came up with is not half bad given that time frame. We will probably have much better COVID vaccines in a few years.

Re: How many microbes does it take to make you sick?

#70

Post by avereveard »

PaulKeeble wrote: post #41
gregwebs wrote: post #33

Great to see statistical thinking. There have been a lot of Covid shouting matches because people are trying to reduce things to binary. Masks don’t work! Actually, they work as advertised- only 95% effective at best (and a cloth mask may be 30%), not a binary protected or not. That’s effective at blocking particles. You are still guaranteed to get some virus particles. They are going to be in your respiratory tract…

Actually N95 is AT LEAST 95% effective. 95% is its worst case performance on a PM2.5 sized particle, at all other particle sizes it is better than 95% usually considerably. We also have N99 masks and even P100 respirators which do an even better job. We just need to start using them. We also need to educate ourselves how to fit and fit test a mask because if its leaking its not giving you that level of protection.

I think that's about the material itself, then at the mask face interface you get all kinds of sealing issues
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