"Germs"

[Angus McPresley]

The advertising consists mostly of statements to the effect that the solution "kills 99.99% of germs" (or harmful germs).

I was living in Singapore when the whole SARS thing hit. At one place where I used to go get ice cream, all the employees wore masks, and they had a sign up that was hyping some new anti-bacterial agent they were using to clean their equipment, in defense of SARS. Which would have been really helpful if SARS was a bacteria.

 

[Skeptic Ginger]

Did you know that during the SARS epidemic a common practice in the affected Asian countries was to go around spraying vinegar in the air?

As far as the masks, even though the particle size the masks filter are larger than viruses, SARS being mostly droplet spread was actually effectively stopped by N95 masks. Those masks are better than the surgical masks seen in most news photos of people in Asia but not my all that much. A surgical mask would likely prevent some SARS cases. The vinegar, however, would have most likely had no effect.

 

[Niobe]

I often wonder how much water and paper products we use in our almost-compulsive handwashing after using the toilet. I mean, how dirty are you going to get?

I read a story about a guy doing a school project about the effectiveness of toilet paper, by wrapping the hand with a number of sheets and seeing if bacteria penetrated them, by unwrapping and swabbing the hand. E-coli got through 1000 sheets of paper.

 

[Skeptic Ginger]

That is interesting, because they are in a serious minority view.

I'll trump the CDC with the EPA, whose comprehensive list of disinfectants effective against norovirus, include only sanitisers with chlorine compounds - not one alcohol-only gel.

I'll have a bet the CDC has just made a simple oversight on this one.

I tried to tell you the Virginia State public health article explained what the CDC was going by and what Virginia's objections were to the rationale. I'm sorry you didn't bother to read it, it would have saved you some time.

It does go to show you, however, why it is easy to think a study is more conclusive than it really is. If you were unaware that the CDC was using a substitute virus in their studies you could easily believe the studies were direct studies on Norovirus itself.

Until recently labs were unable to grow noroviruses to do in vitro testing. The CDC decided to use a substitute virus as the testing agent. The Virginia public health did not feel the substitute viruses were closely enough related to consider the data reliable.

But You also have to be careful to look at the whole picture and not just go by one aspect, in this case in vitro effectiveness of the hand gels. Because in addition to in vitro testing, there are in vivo studies that evaluated the effectiveness of the hand sanitizers. I thought I linked to one study I just saw as I was web surfing that evaluated the rate of norovirus organisms transfered from hands to lettuce and found that 9% were transferred with no treatment. Less than 1% with handwashing and a little more but still less than 1% with the hand gels. So in real life tests, the hand sanitizers were effective in at least decreasing the transfer of norovirus from hands to food. I didn't post the link and now cannot backtrack to it. However, I found similar studies.

Comparative Efficacy of Alcohol-based Hand Sanitizers and Antibacterial Foam Handwash against Noroviruses Using The Fingerpad Method

The results also show it is feasible for an alcoholbased hand sanitizer to give significant NV removal on contaminated fingers. This new synergistically formulated hand sanitizer is therefore a viable option to reduce the spread and risk of NV in food service or other settings.

Studies of Norovirus Infectivity and Persistence

Our studies of handwash agents indicated that liquid soap and water were more effective that an alcohol-based hand sanitizer for removing Norwalk virus RNA from the fingerpads of human volunteers. Further experiments suggest that a hand sanitizer with 70% alcohol Further experiments suggest that a hand sanitizer with 70% alcohol was more effective than a 62% alcohol-based hand sanitizer and can significantly reduce NV RNA on fingerpads. was more effective than a 62% alcohol-based hand sanitizer and can significantly reduce NV RNA on fingerpads.

However, the article does note: "The reliability of disinfectants other than those containing chlorine to kill norovirus is uncertain, so that the use of hypochlorite solutions is recommended for use whenever possible."

But chlorine is too hard on the skin and skin breakdown is associated with a huge increase in organisms growing on one's skin. So what benefit is it to know chlorine is better against norovirus?

You really have to look at the whole picture here, which is, hand washing is better, but the gels are better than nothing if there is no access to running water.

Also to throw into the mix:

University of North Carolina, (page 40) using calicivirus as a surrogate norovirus found that ethanol gel is only effective after 10 minutes' immersion. That would make 20 seconds of rubbing it on your hands fairly useless. Note also that that was 75% alcohol solution - 50% stronger than most gels.

The products noted in the studies I linked to were 62 and 70% respectively. If you just read the labels you can find the same concentrations easily in the supermarkets or drug stores.

 

[Skeptic Ginger]

From Skeptgirls post #54 above:
...None of the studies we've seen here separate the better hand hygiene from the actual use of the alcohol rubs. And with out that separation, there is no evidence that the alcohol does anything beneficial. ....

Yes they did. Go back and look again.

 

[Skeptic Ginger]

I read a story about a guy doing a school project about the effectiveness of toilet paper, by wrapping the hand with a number of sheets and seeing if bacteria penetrated them, by unwrapping and swabbing the hand. E-coli got through 1000 sheets of paper.

Sounds like he either used soaking wet paper or he didn't have clean hands to start with.

Wet bandages and other materials actually act like a wick. A wet bandage is much worse than no bandage. I would think the same applied to toilet paper. Otherwise, bacteria do not walk. So there is no reason they would travel through dry paper.

 

[jimbob]

I read a story about a guy doing a school project about the effectiveness of toilet paper, by wrapping the hand with a number of sheets and seeing if bacteria penetrated them, by unwrapping and swabbing the hand. E-coli got through 1000 sheets of paper.

Sounds like he either used soaking wet paper or he didn't have clean hands to start with.

Wet bandages and other materials actually act like a wick. A wet bandage is much worse than no bandage. I would think the same applied to toilet paper. Otherwise, bacteria do not walk. So there is no reason they would travel through dry paper.

I don't know if it was anywhere else other than the UK, but a lot of my grandparent's generation used to use toilet paper like
this, or equivalent. It also seemed to be used in municipal toilets too, but no more.

If you are unfamiliar with this, it is very similar to greasproof paper: "soft and strong".

 

[Skeptic Ginger]

"Medicated"? Sounds like the same marketing gimmick as we see here. They are putting disinfectants into all sorts of products because it sells, but not because it does anything.

 

[Darat]

Grandparent's generation! You young whippersnapper that was the toilet paper used in my schools until the 80s!

 

[The Atheist]

I was living in Singapore when the whole SARS thing hit. At one place where I used to go get ice cream, all the employees wore masks, and they had a sign up that was hyping some new anti-bacterial agent they were using to clean their equipment, in defense of SARS. Which would have been really helpful if SARS was a bacteria.

Excellent!

I read a story about a guy doing a school project about the effectiveness of toilet paper, by wrapping the hand with a number of sheets and seeing if bacteria penetrated them, by unwrapping and swabbing the hand. E-coli got through 1000 sheets of paper.

"Holy crap" I figured would be an appropriate comment. Lucky the little buggers aren't motile!

It does go to show you, however, why it is easy to think a study is more conclusive than it really is. If you were unaware that the CDC was using a substitute virus in their studies you could easily believe the studies were direct studies on Norovirus itself.

No, in fact I did read it, but since you had as well, I couldn't see the point in covering it bit by bit.

To the best of anyone's knowledge, ethyl alcohol is inadequate at killing norovirus.

Do you dispute that? It seems to be the only issue of contention here.

You really have to look at the whole picture here, which is, hand washing is better, but the gels are better than nothing if there is no access to running water.

This is exactly what I said.

The products noted in the studies I linked to were 62 and 70% respectively. If you just read the labels you can find the same concentrations easily in the supermarkets or drug stores.

There are three on the market here, with 53-55%.

The other point you neglect to mention is that the products in the first studies are measured against rinsing only with running water, and rate about the same effectiveness as rinsing. I don't know how many times more effective proper washing is than rinsing, but I suspect it's a significantly large amount.

The second study notes that:

"Our studies of handwash agents indicated that liquid soap and water were more effective that an alcohol-based hand sanitizer for removing Norwalk virus RNA from the fingerpads of human volunteers."

Can I admit to being entirely confused as to what you're arguing about since your links all tend to agree with me?

 

[jimbob]

Darat, outside municipal institutions, did you ever see it in anyone's home if they weren't of your grandparent's generation?

"Medicated"? Sounds like the same marketing gimmick as we see here. They are putting disinfectants into all sorts of products because it sells, but not because it does anything.

I think the main factor is that it was pretty much like "greaseproof" (slight misnomer in thic context ) paper, so really didn't "let stuff through".

I saw it in the compo ration packs when i was in the CCF... and it sounds like the stuf in the US MRE packs:

The United States Army has long been concerned with so-called natural functions. It is the subject of many colorful army acronyms and nicknames. Particularly on point is the so-called "John Wayne" which, among other things, refers to the toilet paper from the MRE because "it's rough, it's tough, and it don't take **** from nobody." See List of U.S. Army acronyms and expressions.

 

[casebro]

Yes they did. Go back and look again.

Can you do me the favor of pointing out the part in any study where they counted hand washings? Or any other data to see whether the sanitizer presence did or did not lead to more hand washing?

I must have missed it.

 

[blutoski]

Nope, I can't agree with "probably better than washing".

Proper handwashing and drying: (which I'm surprised hasn't been mentioned yet - dry your hands on a dirty towel, may as well not bother) is clearly the best option.

Alcohol-based sanitisers - definitely better than nothing, but not a complete defence, nor as good as a serious hand wash.

Sorry, that's my fault: I worded that badly. I should have said: "probably better than washing by itself."

 

[blutoski]

It's pretty hard to avoid antibacterial soaps. While they are not necessary in the home, you can't find many hand soaps these days (in the US anyway) that do not contain triclosan.

I decided that was not a battle I wanted to waste any of my time on.

I'll pick up the slack. This is one issue I've been pursuing somewhat actively.

It's a priority thing. No skeptic should be expected to boil the ocean.

Actually, the current issue of SI has an article about prioritization. I found an online version at encyclopedia.com (I don't know why?): [Skeptical ethics--what should we investigate?]

 

[Skeptic Ginger]

Ooops! We need to clarify something here and I should have remembered it but didn't. The EPA only approves surface disinfectants. The FDA is the regulating body for any products used on skin. No wonder your EPA site didn't mention alcohol based hand sanitizers, TA.

In looking for a list of products to check the concentration, (which in all products I found was 60-95%), I found this interesting little tidbit. Turns out the EPA tests product effectiveness for norovirus the same way the CDC does, they use a stand in.

Apparently, all the EPA protocol for testing products against norovirus uses "Feline Calicivirus (FCV), a surrogate virus for Norovirus" just like the CDC does. All those EPA approved products in your link, TA, were tested using FCV.

 

[Skeptic Ginger]

And, according to the CDC site, as I said already, they recognize the limitations of the product tests.

It should be noted that evidence for efficacy of disinfectants against norovirus are usually based on data of efficacy against feline calicivirus (FCV) as a surrogate for norovirus. However, feline calicivirus (a virus of the respiratory system in cats) has different physio-chemical properties to norovirus and there is debate on how well data on inactivation of FCV reflects efficacy against norovirus.

Some further information from the same link:

Alcohols have excellent in vitro germicidal activity against gram-positive and gram-negative vegetative bacteria, including multidrug-resistant pathogens (e.g., MRSA and VRE), Mycobacterium tuberculosis, and various fungi (120--122,124--129). Certain enveloped (lipophilic) viruses (e.g., herpes simplex virus, human immunodeficiency virus [HIV], influenza virus, respiratory syncytial virus, and vaccinia virus) are susceptible to alcohols when tested in vitro (120,130,131) (Table 1). Hepatitis B virus is an enveloped virus that is somewhat less susceptible but is killed by 60%--70% alcohol; hepatitis C virus also is likely killed by this percentage of alcohol (132). In a porcine tissue carrier model used to study antiseptic activity, 70% ethanol and 70% isopropanol were found to reduce titers of an enveloped bacteriophage more effectively than an antimicrobial soap containing 4% chlorhexidine gluconate (133). Despite its effectiveness against these organisms, alcohols have very poor activity against bacterial spores, protozoan oocysts, and certain nonenveloped (nonlipophilic) viruses.[ Noroviruses (genus Norovirus, family Caliciviridae) are a group of related, single-stranded RNA, nonenveloped viruses]

Numerous studies have documented the in vivo antimicrobial activity of alcohols. Alcohols effectively reduce bacterial counts on the hands (14,121,125,134). Typically, log reductions of the release of test bacteria from artificially contaminated hands average 3.5 log10 after a 30-second application and 4.0--5.0 log10 after a 1-minute application (1). In 1994, the FDA TFM classified ethanol 60%--95% as a Category I agent (i.e., generally safe and effective for use in antiseptic handwash or HCW hand-wash products) (19). Although TFM placed isopropanol 70%--91.3% in category IIIE (i.e., insufficient data to classify as effective), 60% isopropanol has subsequently been adopted in Europe as the reference standard against which alcohol-based hand-rub products are compared (79). Alcohols are rapidly germicidal when applied to the skin, but they have no appreciable persistent (i.e., residual) activity. However, regrowth of bacteria on the skin occurs slowly after use of alcohol-based hand antiseptics, presumably because of the sublethal effect alcohols have on some of the skin bacteria (135,136). Addition of chlorhexidine, quaternary ammonium compounds, octenidine, or triclosan to alcohol-based solutions can result in persistent activity (1).

Alcohols, when used in concentrations present in alcohol-based hand rubs, also have in vivo activity against several nonenveloped viruses (Table 2). For example, 70% isopropanol and 70% ethanol are more effective than medicated soap or nonmedicated soap in reducing rotavirus titers on fingerpads (137,138). A more recent study using the same test methods evaluated a commercially available product containing 60% ethanol and found that the product reduced the infectivity titers of three nonenveloped viruses (i.e., rotavirus, adenovirus, and rhinovirus) by >3 logs (81). Other nonenveloped viruses such as hepatitis A and enteroviruses (e.g., poliovirus) may require 70%--80% alcohol to be reliably inactivated (82,139). However, both 70% ethanol and a 62% ethanol foam product with emollients reduced hepatitis A virus titers on whole hands or fingertips more than nonmedicated soap; both were equally as effective as antimicrobial soap containing 4% chlorhexidine gluconate in reducing reduced viral counts on hands (140). In the same study, both 70% ethanol and the 62% ethanol foam product demonstrated greater virucidal activity against poliovirus than either non-antimicrobial soap or a 4% chlorhexidine gluconate-containing soap (140). However, depending on the alcohol concentration, the amount of time that hands are exposed to the alcohol, and viral variant, alcohol may not be effective against hepatitis A and other nonlipophilic viruses. The inactivation of nonenveloped viruses is influenced by temperature, disinfectant-virus volume ratio, and protein load (141). Ethanol has greater activity against viruses than isopropanol. Further in vitro and in vivo studies of both alcohol-based formulations and antimicrobial soaps are warranted to establish the minimal level of virucidal activity that is required to interrupt direct contact transmission of viruses in health-care settings.

 

[Skeptic Ginger]

I'll pick up the slack. This is one issue I've been pursuing somewhat actively.

It's a priority thing. No skeptic should be expected to boil the ocean.

Actually, the current issue of SI has an article about prioritization. I found an online version at encyclopedia.com (I don't know why?): [Skeptical ethics--what should we investigate?]

The article includes one of my priorities, of course that's also my field..

Judging by reports in the news, two types of belief seem to be most dangerous and cause the most suffering. One type is belief in modern alternative medicine, which claims to be a valid substitute for mainstream treatment. Again and again, one hears of children whose parents have rejected mainstream medicine--with which the prognosis was good--and opted for alternative "cures" that have not worked (Hyde 2001; Stickley 2002). It is horrific to learn of children dying of cancer and malnutrition because their parents could not distinguish well-evidenced from poorly evidenced claims about health. Clearly, the more skeptical work that can be done here, the better.

The second priority they note is psychic counseling. I can see lots of harm there but I think the article overlooks the harm in anti-science movements like objections to evolution theory and the article also misses one other key priority. That is teaching critical thinking itself. The "teach a man to fish" philosophy is a high priority in my book.

But I am confused as to why antiseptics in OTC hand washing products would be a priority? They are not causing the worst antibiotic resistance, they are cheap, they are not very harmful, and they are not being substituted for something more effective. Perhaps you know of a hazard they are creating that I am unaware of?

 

[Skeptic Ginger]

From Skeptgirls post #54 above:

"Furthermore, the availability of bedside alcohol-based solutions increases compliance with hand hygiene among health care workers."

None of the studies we've seen here separate the better hand hygiene from the actual use of the alcohol rubs. And with out that separation, there is no evidence that the alcohol does anything beneficial.

My summation: The brightly colored plastic dispensers make excellent reminders to use good hand hygiene.

We don't seem to have a smilie to indicate a request for spoon feeding.

A Randomized, Controlled Trial of a Multifaceted Intervention Including Alcohol-Based Hand Sanitizer and Hand-Hygiene Education to Reduce Illness Transmission in the Home

We also performed a preplanned stratified analysis to assess whether the rate of respiratory illness transmission in intervention families was associated with amount of sanitizer use. Primary caregivers reported using the hand sanitizer with a median frequency of 5.2 times per day. Fifty-five (38%) of the intervention families used >2 oz of hand sanitizer per 2-week period (which corresponds to ~60 pushes [1 mL each] from a pump bottle, or 4–5 uses per day). We compared secondary respiratory illness rates in these families with rates in families who used ≤2 oz per 2-week period. Adjusting for the same covariates as in the primary model, the IRR of secondary respiratory illness for those who used the larger amount of hand sanitizer was 0.81 compared with those who used the smaller amount (95% CI: 0.65–1.09; P = .06). In addition, comparing each stratum within the intervention group with control families, those who used the larger amount of hand sanitizer had an IRR of 0.83 (95% CI: 0.60–1.17) for secondary respiratory illness, whereas those who used the smaller amount had an IRR of 1.02 (95% CI: 0.74–1.41). This dose-response relationship was not observed for GI illness; the adjusted IRR for secondary GI illness was similar in those who used >2 oz of hand sanitizer per 2-week period compared with those who used ≤2 oz (IRR: 0.93; 95% CI: 0.21–4.16). However, the small numbers of secondary GI illnesses make investigation of such a trend difficult.

A systematic review on the effectiveness of alcohol-based solutions for hand hygiene

All studies were assessed as having adequate methodological quality. Results of this systematic review supported that alcohol-based hand rubbing removes microorganisms effectively, requires less time and irritates hands less often than does handwashing with soap or other antiseptic agents and water. Furthermore, the availability of bedside alcohol-based solutions increases compliance with hand hygiene among health care workers.

 

[Lensman]

I used to work in a coal mine, there were no toilets or hand washing facilities down there, if you needed to "take a dump", you'd find some out of the way place & do your business, wiping with whatever was at hand & no way of washing your hands afterwards. There was also no canteen or special eating place, you ate your sandwiches where you could get room to sit down, your hands would be black with coaldust & whatever was mixed with it. I have no allergies & rarely catch a cold/flu.

 

[casebro]

We don't seem to have a smilie to indicate a request for spoon feeding.

A Randomized, Controlled Trial of a Multifaceted Intervention Including Alcohol-Based Hand Sanitizer and Hand-Hygiene Education to Reduce Illness Transmission in the Home

A systematic review on the effectiveness of alcohol-based solutions for hand hygiene

The study in your first quote does not allow for the possibility that folks who use more HS would also wash hands more. A very likely possibility. And even the title states that they included more education towards increased hand washing.

Your second link is one that proves MY point, with the last sentence that is included :

"Furthermore, the availability of bedside alcohol-based solutions increases compliance with hand hygiene among health care workers."

So you still have not come up with anything to refute my idea that the main activity of HS stations is to remind people to wash hands more often, that HS accomplishes very little by directly killing anything.

But I'm still open. That second study hinted thart somebody kept track of 'hand hygiene' with the "increases compliance with hand hygiene among health care workers." But it was a meta study. Which of it's studies actually counted hand washings? That one in particular could prove that HS is ineffective.