

How Well Do Hand Sanitizers Work? - mhb
http://www.slate.com/id/2245896/?from=rss

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dabent
"In 1847, Hungarian doctor Ignaz Semmelweis discovered that washing one's
hands with chlorine between deliveries practically eliminated fatal infections
among laboring women. (His colleagues ignored him and later committed him to a
mental hospital, where he was beaten to death by guards.)"

There's better reading on that here (link found in the original article):
<http://www.semmelweis.org/about/dr-semmelweis-biography/>

It's amazing how stubborn we can be to changes, even positive changes.

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jessriedel
"Today, numerous modern studies show that in randomized trials, meticulous
hand-washing, when coupled with other infection control measures like surgical
draping and universal gloving, reduce the rate of life-threatening infections
during surgery and intensive care unit stays.

But in hospitals, outside of these clinical trials, just half of doctors and
nurses regularly clean their hands before patient care, despite widespread
publicity."

This is a silly comparison. During surgery (when people are literally split
open) and in ICUs (when their body is profoundly damaged), the human body is
unnaturally and incredibly sensitive to infection. If you've ever witnessed a
surgery, you'd know that surgeons are insanely, mind-bogglingly obsessive-
compulsive about washing their hands and keeping a sterile operating room.

But 99% of people in the hospital or doctor's offices are not so compromised,
so it's not surprising that doctors and nurses aren't religious about hand
washing "before patient care".

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RyanMcGreal
I've talked to doctors about this, and they point out that if they actually
sanitized every time they come into contact with a patient their hands would
get so dry the knuckles would start bleeding when they bent their fingers.

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jrockway
I hear there is this stuff called "moisturizer", which restores the moisture
and oils that have been washed away by soap.

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RyanMcGreal
Of course, given that the moisturizer is unsanitary, the doctors and nurses
would immediately have to wash it off again. :/

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jrockway
Sounds like a problem that could be solved. It's not all bacteria and viruses
that need to be killed completely, it's mostly MRSA that is the problem. That
probably doesn't live in moisturizing lotions; and once you've removed it from
your hands, it's not going to come back until your touch it again.

Also, what about just wearing rubber gloves?

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goodside
The studies mentioned don't show that _using_ hand sanitizers is ineffective,
just that _mailing_ the sanitizers to people along with informational
pamphlets is ineffective. If you actually read the first study they report
finding a significant (though small) effect on respiratory infections for
families that claimed to have actually used the products.

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ErrantX
I've always wondered whether the growing modern obsession with bug killing and
so forth might be counter productive.

Has anyone seen any studies they can recommend into the long term effect on
our immune system?

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alexandros
What I'm more worried about is the claim that they kill 99.9% of germs. This
would mean that the most resistant 0.1% get all the free space to grow. We're
not disinfecting our world, we're creating evolutionary pressure on the germs
to become resistant to our countermeasures.

~~~
ErrantX
Does that mean they kill 99.9% of known germ types (i.e. some are resistant).
Or that it is able to kill 99.9% of germs on a known object (i.e. some random
subset of germs will escape destruction for whatever reason).

I suppose the former but I've never researched.

~~~
alexandros
That's interesting. I always interpret it to be 99.9% of the population on a
given surface. It could be read as types also I guess.

EDIT: the article posted here <http://news.ycombinator.com/item?id=1031922>
seems to support the 'types' theory, although it also casts significant doubt
on the validity of the claims.

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brandon272
There are a lot of misconceptions about the effectiveness of various hand
sanitizers. What's important to know: common hand based sanitizers with a ~70%
concentration of alcohol, when used properly and when left on the hands to dry
(some people use the sanitizer and then wipe) are extremely effective at
killing exposed bacteria, without the risk of developed resistance.

~~~
Mankhool
This is my first winter using (employer supplied) hand sanitizer. I have to
say that so far, I haven't had any seasonal illinesses - and I don't take flu
shots either - so I believe it has helped (along with regular hand washing and
wearing gloves whenever I go out).

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dsplittgerber
Hand sanitizers are a great example of fear-based marketing, which is very
effective, just like fear-based politics.

~~~
techiferous
I guess our brains are wired so that emotional content trumps informational
content. (Which also explains why there always seems to be several "dramatic"
posts on the front page of Hacker News like Calacanis vs. Cutts.)

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JoeAltmaier
Used to use alcohol (basis of hand-sanitizer effectiveness) to sterilize in
hospitals (before autoclave). Had to soak for 20 minutes in pure alcohol. What
difference can rubbing dilute alcohol onto your hands for 3 seconds do?

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gjm11
There might be a difference in how thoroughly you need to sterilize something
(1) before bringing it into prolonged contact with someone's bloodstream,
internal organs, etc., versus (2) before briefly touching your food / blowing
your nose / ... with it.

~~~
JoeAltmaier
No, no difference really, if your goal is to avoid transmitting a virus.

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dgordon
Yes there is. It's like the difference between going to Volgograd as a tourist
today and going to Stalingrad as a member of the German army in the winter of
1942-43.

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poutine
Ah, a simple metaphor we all can relate to. :)

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dgordon
Yeah, if I had been saying it out loud I would have been grabbing for words
halfway through and would have realized it was a bit overwrought.

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thrdOriginal
I've met Chuck (the first author referenced) a few times, and a couple
interesting germ related items I remember him relating to me: The cleanest
place in a women's bathroom is the toilet seat (nearly half of women wipe it
down before use). The cleanest place in a men's bathroom is the inside door
handle. Bathroom air dryers are the least sanitary - those aerosolized
droplets he mentions in the article are sucked up and blown right onto your
hands. Overall though, he gives the impression of someone who is absolutely
not an obsessive hand washer.

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ax0n
You can count me as one of the unsurprised.

The fact is that the sanitizers only work while moist, and they evaporate
quickly. You'd basically need to bathe constantly in it (which would destroy
your skin, by the way) for it to be effective. After handling raw meat or
between handling infected patients? Sure, good idea. After driving to work? It
won't make a damn bit of difference once you push the elevator button, much
less once you hang out in a co-worker's office or pick up your phone.

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kanwisher
Am I the only person that finds the consistency of Hand Sanitzers just icky, I
really like the feel of soap or am I just getting old ;/

~~~
jrockway
I also hate hand sanitizers. I feel very dirty after using them, and feel the
need to wash my hands. So I just wash my hands and skip the sanitizers.

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hackermom
i wash my hands with soap and hot water every time i get home to my apartment
(after grabbing the door handles of the supermarket etc. etc.), and have done
so since young age. i don't lick my fingers or poke myself in the eye, ear
etc. without having absolutely clean hands. incidentally - and i know
correlation is not always causation - i never get sick. ever. rhinovirus
doesn't get me. calicivirus doesn't get me. no flu has ever gotten me.

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ajju
_no flu has ever gotten me._

 _ever_? I know people say this all the time, but are you sure, you have never
had the flu?

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sjs
I believe them. I'm not quite that fastidious about washing my hands after
being out in public, and I've only had a flu once when I was 10-12. It was a
24-hour flu and it was very unpleasant, but thankfully that's the only time
I've had it.

I generally don't get sick. I catch a head cold sometimes during the season
but again, it's usually pretty mild and gone the next day.

