Germs

[Southwind17]

So, my missus gives me some Dettol hand wash, you know, the type that you just squeeze on and rub around without rinsing off, that claims to kill 99.99% of germs, and I'm wondering: is it cynical to wonder whether the 0.01% are the dangerous ones, and in any case wouldn't it be better to wash and rinse? It sure feels better - psychologically!

 

[Ziggurat]

So, my missus gives me some Dettol hand wash, you know, the type that you just squeeze on and rub around without rinsing off, that claims to kill 99.99% of germs, and I'm wondering: is it cynical to wonder whether the 0.01% are the dangerous ones, and in any case wouldn't it be better to wash and rinse? It sure feels better - psychologically!

Washing and rinsing is good (and generally good enough), but it's not always available (plus you can apply the alcohol solutions after washing too), whereas the alcohol lotions are very portable. And while there may be some differential between what kinds of bacteria get killed, those alcohol rubs will still kill most of any kind of bacteria they encounter. And yes, the amounts matter. Exposure to a single bacteria is not enough to make you sick. The level of exposure can make a big difference, so you don't need to kill all the bacteria to avoid getting sick, just enough of them.

 

[Southwind17]

Washing and rinsing is good (and generally good enough), but it's not always available (plus you can apply the alcohol solutions after washing too), whereas the alcohol lotions are very portable. And while there may be some differential between what kinds of bacteria get killed, those alcohol rubs will still kill most of any kind of bacteria they encounter. And yes, the amounts matter. Exposure to a single bacteria is not enough to make you sick. The level of exposure can make a big difference, so you don't need to kill all the bacteria to avoid getting sick, just enough of them.

So it's generally quantity not quality that matters? But then some types are worse, like salmonella, yes?

 

[Ziggurat]

So it's generally quantity not quality that matters?

Both matter. If you ingested plague bacteria in the quantities that you ingest the bacteria in active culture yogurts, you'd be in trouble. But the alcohol rubs cut across the entire bacterial spectrum.

 

[Bikewer]

I've listened to a couple of microbiologists on Science Friday who don't think much of the whole idea.
First, ineffective. Our skins are host to a rather extensive fauna and flora, many living below the external layers that these washes might affect.
Secondly, with only a tiny portion of bacteria even remotely dangerous, they fear that broad-spectrum and constant "de-germing" just eliminates the good guys and may actually promote more lethal strains.

 

[~enigma~]

I've listened to a couple of microbiologists on Science Friday who don't think much of the whole idea.
First, ineffective. Our skins are host to a rather extensive fauna and flora, many living below the external layers that these washes might affect.
Secondly, with only a tiny portion of bacteria even remotely dangerous, they fear that broad-spectrum and constant "de-germing" just eliminates the good guys and may actually promote more lethal strains.

So healthcare workers (particularly in hospitals) shouldn't sanitize their hands so they can transfer germs from one patient to the next? Great idea, move healthcare back into the middle ages.

 

[Dymanic]

I carry alcohol gel hand sanitizer pretty much all the time during cold and flu season, and I at least keep it in the car year round. I try to avoid products that include antibacterial agents like Triclosan (not sure if the specific product mentioned is one of these or not). Overuse of these antibacterial agents leads to increased resistance in some bacteria. One significant consequence is that this makes infection control in clinical settings more difficult.

 

[Ziggurat]

I've listened to a couple of microbiologists on Science Friday who don't think much of the whole idea.

I'll do with the doctors on this one. They're the ones to whom such issues have real immediate impact.

Secondly, with only a tiny portion of bacteria even remotely dangerous, they fear that broad-spectrum and constant "de-germing" just eliminates the good guys and may actually promote more lethal strains.

There's something to be said about the overuse of antibiotics, and perhaps even antibacterial soaps. But those instant hand sanitizers mostly use alcohol as the anti-bacterial agent. Bacteria can't really evolve alcohol tolerance the same way they can evolve antibiotic resistance, doing so would probably make them LESS adapted to human hosts (since even while soused, we're a low-alcohol environment), and it wouldn't impact treatment of sick patients anyways (getting them drunk isn't how we combat infections). Furthermore, they're only really used on the hands (since that's what we infect ourselves with), so other cultures of benign bacteria still have plenty of places they can grow and flourish.

 

[Dancing David]

One benefit i have heard is that the lotions just move the oil around your hands as opposed to hand washing.

I like both for different settings. (grade schools are a good place for lots of both.)

 

[Audible Click]

One benefit i have heard is that the lotions just move the oil around your hands as opposed to hand washing.

I like both for different settings. (grade schools are a good place for lots of both.)

Speaking of grade schools, the schools in our area have banned the kids from having the hand cleansers due to the cleansers containing alcohol. Zero Tolerance Policy. I guess they thought the kids might drink the hand cleansers.

 

[casebro]

There doesn't seem to be any placebo controlled study done yet. One with plastic bottles of plain water.

My feeling is that the ever-present plastic bottles act as a reminder to wash up.

Probably a strong, disagreeable perfume in the bottles would do as well. It would remind you not to get hands near faces without washing first.

 

[Dancing David]

Speaking of grade schools, the schools in our area have banned the kids from having the hand cleansers due to the cleansers containing alcohol. Zero Tolerance Policy. I guess they thought the kids might drink the hand cleansers.

Well, I suppose some might, but when you can buy crack, why bother?

 

[tesscaline]

Speaking of grade schools, the schools in our area have banned the kids from having the hand cleansers due to the cleansers containing alcohol. Zero Tolerance Policy. I guess they thought the kids might drink the hand cleansers.

This seems like a very odd policy. Have they banned wet-naps too? Because the chemical content (i.e. rubbing alcohol) is the same. Or are the people making these decisions too stupid to know that rubbing alcohol isn't the same as drinking alcohol?

 

[shadron]

Like everything else in life, using these anti-microbials is a trade-off. You're balancing your desire to have no germs in your vicinity with allowing your immune system to handle in it the way it has become accustomed to (evolved for) for millions of years. When infuenza (such as the current H1N1) is rampant, then it may be a good idea to use the stuff after you touch anything in a public area; one of the experts I heard suggested that a superb way to spread H1N1 among the world population would be to infect the finger print scanners at the airports for international flights.

So, my suggestion would be to use the stuff if you are out and about during flu season, particularly if you have a habit (as I do) of rubbing your eyes. When home, or when diseases aren't threatening, don't use it so much.

One of the effects of killing off benign and neutral bacteria, both internally and externally, is to open up environmental niches for viruses, fungi and yeast. This results, in babies, in thrush, a fungal mouth infection often seen while on an antibiotics course. And then, there is the now-familiar "survival of the fittest" effect, where the only bacteria that live through a use of an antibiotic (internal or external) is the bacteria you least want to encourage, and you've just eliminated all of its competition. You fight that attack through either not using an antibiotic, or using the antibiotic until chances are you've killed 100% of the bacteria exposed to it.

As with any antibiotic, use it when the risk is high, and otherwise don't.

 

[Audible Click]

This seems like a very odd policy. Have they banned wet-naps too? Because the chemical content (i.e. rubbing alcohol) is the same. Or are the people making these decisions too stupid to know that rubbing alcohol isn't the same as drinking alcohol?

I don't know about the wet naps but it wouldn't surprise me if they were banned. Their zero tolerance policy even extends to not allowing Chapstick, as far as I'm concerned the whole zero tolerance policy is a mess.

 

[Ysidro]

So healthcare workers (particularly in hospitals) shouldn't sanitize their hands so they can transfer germs from one patient to the next? Great idea, move healthcare back into the middle ages.

No.

Fortunately, no one even thought of this except you.

 

[~enigma~]

No.

Fortunately, no one even thought of this except you.

Next time you are in the hospital tell your doctor, nurse and tech not to sanitize their hands before touching you. Enjoy the nosocomial infection you acquire and hope it isn't MRSA.

ETA - Wonder why there is a term for an idea that is only held by me?

 

[Dymanic]

Because the chemical content (i.e. rubbing alcohol) is the same.

Actually the active ingredient in the alcohol-based hand sanitizers is ethyl alcohol, not ispopropyl.

 

[Bikewer]

The fellows on Science Friday were not talking about clinical settings, they were referring to ordinary everyday situations.

We use a lot of the stuff in police work, for the expected reasons.

I can well remember my mother (born in the 20s) going on and on about "germs". Likely the realization that microbes cause most disease was just coming into the knowledge sphere of the general public back then.
As I began to read about such things, I tried to explain that her extreme "scrubbiness" was not only unneccesary but ineffective.....Didn't make much impact.

 

[tesscaline]

Actually the active ingredient in the alcohol-based hand sanitizers is ethyl alcohol, not ispopropyl.

Hrm. It would seem that you're correct. I was under the impression that it wasn't ethyl, but that goes to show you how recently I've actually looked at a bottle of purell...

In any case, drinking purell (if that's really the concern, that kids would use it to get drunk with) is still not advised, and you're supposed to call poison control and seek medical attention immediately if you swallow it.

Of course, given that the school district also doesn't allow chapstick (seriously? what in the heck?), it would seem that they have put NO thought into the matter at all...