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Some Bacteria Are Becoming 'More Tolerant' of Hand Sanitizers, Study Finds
- xbryanx 8y agoI always find it fascinating how much the mechanical aspect of hand-washing makes it more effective than many other methods of sterilization.
- hammock 8y agoSure it does. You don't shampoo your hair without running your fingers through it, right?
- themarkn 8y agoMan if we shampooed our hair before eating our hands would be extremely clean.
- hutzlibu 8y agoyou want to eat your clean hands, or eat with you clean hands... I like the latter actually. Gives more connection to what you are eating
- dragosmocrii 8y agouse commas
- nashashmi 8y agoif we shampooed our hair before eating our hands would be extremely clean Can someone identify whether this is correct?
- avryhof 8y agoThat's fine. Some bacteria is actually good for you. Even trace amounts of "bad" bacteria will help build your immune system so you don't need to kill all bacteria.
- nerdponx 8y agoThis is about hospital infections, not the hygiene hypothesis.
- tootie 8y agoI also have yet to see any evidence that hygiene hypothesis is true or leads to better long-term health outcomes.
- kristiandupont 8y agoThe book An Epidemic of Absence presents a pretty compelling case, I recommend it.
- gruez 8y agoa 400 page (tl;dr), non-peer reviewed book (no endorsements from the scientific community) is probably not the best evidence to present.
- Herodotus38 8y agoThere's actually pretty good evidence now that childhood sanitation is correlated with the incidence of Acute Lymphoblastic Leukemia (ALL). Edit: accidentally wrote inversely Here is a pretty good overview: https://www.medscape.com/viewarticle/897242 https://www.medscape.com/viewarticle/897242 Note that this is a little different than the usual interpretation of the hygiene hypothesis.
- anonytrary 8y agoThat's true, but when it comes to hospitals, you want to try and minimize all bacteria. Your skin may be a very protective organ, however if you get those same bacteria in a wound, it could lead to dangerous infection.
- mrfusion 8y agoI wonder what the mechanism is? Biofilm?
- dfsegoat 8y agoEvolution and adaptation fundamentally ^. Bacterial growth is essentially logarithmic / exponential - so all it takes is a few bacterial cells to have a chance mutation which affords the resistance to $THING, and the population is back to growing fine in the presence of $THING, and is ready to spread those beneficial mutations with other bacteria (in a hospital drain system for instance [1,2]). $THING could be antibiotics, hand sanitizer - etc. This basic principle is taught by example in every intro to microbiology / molecular bio laboratory course. 1. https://en.wikipedia.org/wiki/Horizontal_gene_transfer https://en.wikipedia.org/wiki/Horizontal_gene_transfer 2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4117541/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4117541/ (^) Edit after downvotes: My only point was that the underlying mechanism is somewhat irrelevant - bacteria will always find a way to break down things humans put in their environment, even Nylon or radiation.
- tootie 8y agoBut this is equivalent to humans evolving to drink lava isn't it?
- nashashmi 8y agoAnd humans becoming more tolerant of the heat and regenerating cells and tissue quickly enough to survive.
- dfsegoat 8y agoI see what you are getting at - but it's all about pressure and selection. For instance Sickle Cell anemia is hypothesized to actually be a defense we evolved against malaria: https://en.wikipedia.org/wiki/Human_genetic_resistance_to_malaria https://en.wikipedia.org/wiki/Human_genetic_resistance_to_ma... People that had that mutation were better able to fight off malarial infections in those environments where it was prevalent - and those genes now are passed on specifically in certain ethnicities, etc.
- pard68 8y agoI am impressed. I was under the impression that this stuff works because alcohol kills basically everything. Looks like we need to start washing with Everclear now.
- dx87 8y agoThat's what I thought as well. When I took a biology class in college we asked why hand sanitizer that kills 99.9 percent of germs is fine, but excessive use of antibiotics breeds super germs. The professor told us that it just destroys it at a molecular level, so there's nothing to resist, it'd be like trying to develop a resistance to being torn apart by a black hole.
- okmokmz 8y agoThat's my understanding as well. Bacteria cannot survive in alcohol because the lipid structure in their cell membranes are disrupted and their proteins become denatured
- lima 8y agoIt's known that some bacteria can survive just fine in moderate concentrations (the paper points out lactic acid bacteria in sake, surviving at more than 18%) by means of membrane transporters. The authors suggest that insufficient concentrations could allow tolerant bacteria to survive. > As alcohol tolerance increases, we hypothesize that there will be skin surfaces in contact with alcohol-based hand rubs or inanimate surfaces in contact with other alcohol-based cleaning agents that do not receive the maximum biocide concentration or contact time required for effective bacterial killing.
- cup-of-tea 8y agoHand sanitisers in offices etc. should be outlawed. There's simply no reason for their existence and using them probably weakens your immune system anyway. They are useful for situations like camping but that is all.
- sol_remmy 8y agoThey should be outlawed for camping too... the importance of keeping bacteria from growing immune outweighs the small risk of getting a stomach bug while camping Sanitizer should ONLY be legal for use in hospitals
- cup-of-tea 8y agoYeah, you're probably right. We've used soap for centuries and it works very well.
- mrfusion 8y agoWe should ban soap too so bacteria don’t get immune to that.
- atomic77 8y ago> The researchers used different strengths of alcohol concentrations to combat the bacteria, starting with 23 percent. Eventually, at a 70-percent alcohol mixture, the bacteria were conquered. Typically, hand sanitizers are 60 percent alcohol. Is it simply a matter of using higher concentrations of alcohol? Or is it possible that bacteria could evolve resistance right up to 100%?
- hcurtiss 8y agoIt’s not like an antibiotic. At sufficient concentrations, it seems like the lipids in the cell membrane would simply dissolve.
- Fomite 8y agoOne of the problems with alcohol-based hand sanitizers is that there's a war between "Kills Bacteria" and "Demolishes Your Hands" - one of the major problems in hospitals is compliance, and the harsher the alcohol concentration, the harder it is to get people to use it.
- notanote 8y agoA 70% solution is considered the most effective. Higher concentrations of alcohol (over 90% especially) evaporate more quickly, reducing contact time. Also, they work too quickly. By coagulating the outer proteins of bacteria instantly, they form a protective layer that actually stops the alcohol from penetrating further.
- mmt 8y agoAlthough I agree that over 90% is less effective (and your explanation is clearer than mine [1]), do you have a reference for 70% (and is it w/w or v/v?) is the most effective? Last I read up on it, I found the number to be closer to the European hospital standard of 85%, although I don't have the reference in my bookmarks, nor do I recall if it was reflect of scientific consensus, if one even exists on the topic. [1] https://news.ycombinator.com/item?id=17684070 https://news.ycombinator.com/item?id=17684070
- ars 8y ago
- petermcneeley 8y ago"have hard shells that make it difficult for alcohol to kill them" It is likely that such adaptation has a cost. Is alcohol resistant bacteria more benign inside the human body?
- jimmy1 8y agoAlso, with only my rudimentary understanding of microbiology, wouldn't just scrubbing your hands together vigorously, which is already recommended, overcome that?
- Florin_Andrei 8y agoSoap and water should work better every time.
- jonhendry18 8y agoAccess to a sink isn't always convenient or possible.
- Florin_Andrei 8y agoSure, but dying is even less convenient.
- Fomite 8y agoBiofilms and sporulation are enough of a benefit in hospital environments that I doubt it confers much of a fitness detriment, and there's no promise that even if it does, that that comes in the form of decreased virulence.
- TacticalMalice 8y agoThose shells are temporary; They talk about endospore forming bacteria. They are very hardy and "dormant", but can reactivate given the right conditions. Bacillus cereus for example can survive rice cooking in the spore form, then reactivate and poison you if you leave the cooked rice out of the fridge long enough.
- ohnoesmyscv 8y agoDupe of https://news.ycombinator.com/item?id=17677617 https://news.ycombinator.com/item?id=17677617
- jwilk 8y ago(0 comments)
- bloopernova 8y agoI wish this article had provides a link to a comparison between the different hand sanitizing methods. OK, so alcohol-based sanitizer isn't great. How does it compare to plain old soap and water? What about foaming liquid soap? How does the big gun of Hibiclens work out nowadays?
- AngryData 8y agoSoap and water doesn't directly kill the bacteria, it dissolves the oils and lipids that that they live in and washes them away. Some die, but if bacteria was humans, using soap and water is the equivalent of causing a landslide and just clearing the entire surface of the area of anything but dirt/skin and dumping the people/bacteria off the cliff and down the drain.
- JumpCrisscross 8y ago> it dissolves the oils and lipids that that they live And out of which bacteria membranes are made.
- chiefalchemist 8y agoI think there's a (obvious) difference between anti-bacterials and standard hygiene. We know these organisms adapt, just as they did to (oral) antibiotics. Is there any biological reason why hand sanitizers would be any different?
- Fomite 8y agoThe key to all adaptive mechanisms is that they have to not kill the bacteria as well. The mechanism of action for hand sanitizers is to disrupt the lipid membrane - it's possible no adaptation exists to make a lipid membrane resistance to high concentrations of alcohol (or other surfactants) that also still renders it a workable membrane. The current resistance mechanisms in the study are mostly efflux pumps, which again, may not be expressible to save a bacteria when alcohol is present at volume. Even most antibiotic resistance mechanisms are not actually a binary "Works/Doesn't Work" but rather can fight off the antibiotics at the concentration they're delivered in.
- pkaye 8y agoAs someone who does home dialysis and relies on alcohol hand sanitizers this kind of worries me.
- Fomite 8y agoUse high concentration sanitizer and you should be fine.
- dghughes 8y agoMost people don't use it correctly anyway. You're supposed to soak your hands so they're dripping, rub together and let it evaporate. You see most people just using a small dot on their palms. I've also read about a certain rare bacteria that thrives on a food additive. I cant recall what it was but I remember it was really expensive to make the suddenly a new methods made it cheap. The bacteria rose as the cost of the additive went down.
- dubyah 8y agoC. difficile & trehalose?
- dghughes 8y agoYes it seems it was C. difficile. I was on mobile and it was tedious to look. But now I did a search and the article I linked below mentions "virulent strains of the bacterium Clostridium difficile". A brief snippet >Trehalose is an extremely stable sugar, resistant both to high temperatures and to acid hydrolysis thanks to the glycosidic bond linking its two glucose units. This makes it valuable for high temperature food processing, since it doesn’t lead to browning as part of the Maillard reaction. Speaking of Clostridium difficile. >...they can grow on this sugar while others cannot.’ https://www.chemistryworld.com/news/food-additive-may-have-given-deadly-bacterium-its-chance/3008488.article https://www.chemistryworld.com/news/food-additive-may-have-g...
- jwilk 8y agoText-only version: https://text.npr.org/s.php?sId=635017716 https://text.npr.org/s.php?sId=635017716
- efficax 8y agowe need a new "manhattan" project to tackle the problem of bacterial resistance. Seriously we should be investing hundreds of billions of dollars into research into more effective means of controlling infectious diseases. We're on the brink of reverting to the times before antibiotics where common infections that are now easily treatable will be deadly and debilitating again. It's terrifying.
- chiefalchemist 8y agoBut sadly, this is not new news. Unfortunately, it's not sexy in a political and/or mainstream media sense. No one seems interested in owning the problem. Perhaps, again sadly, the only hope is this becoming a national security issue and the DoD throwing its budget weight at it. But if obesity is any indication, that's not going to be enough.
- refurb 8y agoIt’s concerning, but shouldn’t be terrifying (although the media prefers it to be). Even with highly resistant strains, current antibiotics works in nearly all cases. Physicians are quite careful about reserving the “big guns” for last. In addition, anti-resistance techniques have been effective with some resistant strains actually decreasing in prevalence over the past few years. Do we need to keep researching new antibiotics? Of course. Is it doomsday? No.
- goostavos 8y agoLinks to whatever you're reading that gives you that confidence/understanding? The media has me pretty convinced that we're on the brink of a modern medicine failure
- refurb 8y agoGood place to start: https://resistancemap.cddep.org/AntibioticResistance.php https://resistancemap.cddep.org/AntibioticResistance.php Three out of the six tracked antibiotic have decreasing resistance rates (aminopenicillins, amoxicillin, piperacillin). The last two are front-line antibiotics that have been around for decades. They still work for most infections. It's not evident from these graphs, but prior predictions were rates were going to drastically increase over the past decade. That hasn't born out. Not saying this isn't a public health concern, but it's also not antibiotic armageddon.
- throwawaymanbot 8y agoHand "Sanitizer" is banned In Europe for a reason.
- dev_dull 8y agoWould it be too much just to install little hand washing sinks in front buildings? I don’t need the germs to die. They can live in the sewer all day long. I just want them off my hands.
- Fomite 8y agoThe study is looking in hospitals, where the volume of hand sanitization needs are much higher than the average setting. And where, interestingly, germs living in the sewer are causing problems - biofilms in plumbing can easily recontaminate sink surfaces.
- kevin_thibedeau 8y agoI for one would like to know what happens to the cellulose carrier. It always seemed creepy to me to slather that over your hands, leaving a nice food source for new bacteria once the alcohol evaporates.
- Pica_soO 8y agoI sometimes wonder, if we couldn't make some sort of tailored grave-digger bacterium- hell bent on eating toxins, encapsulating them and get burried with them. Thats how nature does it after all- no matter what spills and kills, something eats something, gets sick and not devoured- falling to the floor, becoming another strange bark layer for the geologists to marvel about.