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Comment by okreallywtf | Hacker News Reader

I hope its not too little too late, we've known about bacterial resistance for decades at this point. Here is hoping animal feed is next.

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You have a common misconception. Antibacterial soaps don't cause bacterial resistance. Antibiotics do, but that's because antibiotics must selectively kill bacteria while inside the human body and without harming human cells.

Antibacterial doesn't really have a precise medical definition, but in practice they're dilute antiseptics. In many centuries of use, bacteria have not developed resistance to antiseptics. There's no danger of them developing resistance to these soaps either

...and even if they did, that wouldn't mean they were magically also resistant to some antibiotic.

So basically, the marketing people wanted something more than "just soap" so they used antiseptics and made up a nicer sounding word: Antibacterial. You have (and perhaps this was the intent of the marketing people) assumed this has something to do with antibiotics.

Antibacterial soaps end up in very dilute concentrations and are used dramatically more than they used to. Sure, these soaps don't use Antibiotics, but having a wide range of Antibacterial substances that continue to work and can be applied to your skin is very useful.

Remember, an autoclave or UV lamp work fine to keep stuff sterile, but they are not safe to put your hand in / under.

It's not a misconception. https://en.wikipedia.org/wiki/Triclosan#Resistance_concerns

That depends on what you mean by "antiseptic".

No bacteria, ever, is going to develop a resistance to 99% EtOH, or 10:1 dilute NaClO. Ever.

Many, many bacteria develop resistance to triclosan.

The FDA just banned the one that sucks.

To quote from a review article[1]: "Antiseptics are biocides or products that destroy or inhibit the growth of microorganisms in or on living tissue". So antibiotics are a type of antiseptic.

>In many centuries of use, bacteria have not developed resistance to antiseptics. There's no danger of them developing resistance to these soaps either

This is not really true. In fact, the substance under question here, Triclosan, is a small 24-atom molecule so, in principle, there's no reason microbes couldn't develop resistance to it.

"TCS inhibits FabI, an enoyl-acyl carrier protein reductase (ENR). The FabI protein catalyzes the elongation cycle in the synthesis of fatty acids, an essential process for cell viability "[2]. Thus, one known mechanism of resistance is to alter the protein that TCS binds to:

"Mutation occurs whereby single or multiple amino acids are changed in the fabI gene, resulting in TCS-resistant FabI proteins"[2].

And it's not even just a matter of "well TCS is ineffective, so why not just leave it alone?". Triclosan is implicated in multi-drug cross resistance:

"In studies done on E. coli and P. aeruginosa, resistance to chloramphenicol and tetracycline increased 10-fold following TCS exposure"[2]. In addition, a survey of Acinetobacter baumanii (an increasingly common opportunistic pathogen found in hospital acquired infections) clinical isolates found that those that could resist low concentrations of TCS also exhibited "increased tolerance to amikacin, tetracycline, levofloxacin and imipenem."[2].

So in fact having TCS everywhere is actively harming our ability to use other effective antibiotics.

[1] McDonnell G, Russell AD. Antiseptics and Disinfectants: Activity, Action, and Resistance. Clinical Microbiology Reviews. 1999;12(1):147-179. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC88911/

[2] Carey DE, McNamara PJ. The impact of triclosan on the spread of antibiotic resistance in the environment. Frontiers in Microbiology. 2014;5:780. doi:10.3389/fmicb.2014.00780. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4295542/

Most antibacterial resistance comes from http://www.fda.gov/ForConsumers/ConsumerUpdates/ucm378100.ht...

Yup that would probably be one of the big thing in the whole antibiotic crisis and just making sure the farm environment is good once you can't rely on just flooding them with antibiotic and keep them alive.

Flooding them with antibiotics isn't just to "keep them alive." It makes them grow bigger (i.e. more meat to sell means more money). This is a big part of the resistance to ending the practice too.

Do you mean the antibiotics keeps them healthy and in turn bigger or antibiotics has some growth hormone type effect?

It makes them grow bigger, like a growth hormone effect. https://en.wikipedia.org/wiki/Antibiotic_use_in_livestock

And the best part is, no one knows why.

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