Good ole’ timey science-off: what’s the best way to wash hands, do sanitizers have a role?

Science is about a world–view of a topic and providing the data to back up that view.

Biology is especially messy.aust.handwashing.oct_.151

International handwashing day was October 15, but I was busy making a mess.

In Australia, the feds have a nice poster and how paper towel is to be used to dry hands, and I’ve never been in a Western country that has more hand driers than paper towel dispensaries.

Proper handwashing requires proper tools.

Ludwig writes in the current issue of Public Understanding of Science (November 2014 vol. 23 no. 8 982-995) to propose a methodological externalism that takes knowledge about science to be partly constituted by the environment. My starting point is the debate about extended cognition in contemporary philosophy and cognitive science. Externalists claim that human cognition extends beyond the brain and can be partly constituted by external devices. First, I show that most studies of public knowledge about science are based on an internalist framework that excludes the environment we usually utilize to make sense of science and does not allow the possibility of extended knowledge. In a second step, I argue that science communication studies should adopt a methodological externalism and accept that knowledge about science can be partly realized by external information resources such as Wikipedia.

Style is important, but content rules.

In this corner, Dr. Keith Warriner of the University of Guelph (that’s in Canada), who writes there are many old-wives tails, rumors and stories that are so ingrained that we don’t know if they are fact or fiction. The list is so long that a popular TV show called “The Myth Busters” is totally devoted to applying science to verify if myths are true or false. The show is for entertainment but it is when myths or non-substantiated knowledge, are actually applied in regulations and guidelines with the thought that someone must have done the science at some point in time.

As many new mothers in the latter part of the 19th century will verify, hand washing has been an essential intervention for minimizing the transfer of pathogens in clinical, food and other environments. The recommended method for washing hands was developed in 1980’s and has not changed significantly through the years. But is the method supported by science?

Myth 1: Antimicrobial soap provides superior hand washing results compared to normal soap

It has been widely accepted that antimicrobial soap is preferred over normal soap for increasing the efficacy of hand washing. Of all the aspects associated with hand washing the comparison of antimicrobial vs. normal soap has been studied to the greatest extent. The general conclusion is that antimicrobial soap supports a marginal increase in the number of bacteria removed from hands. If high inoculation levels are applied to hands then the removal with antimicrobial soap is statistically significantly compared to normal soap. However, with natural skin microflora there is no difference between the efficacy of normal and antimicrobial soap.  

There has been recent research that has suggested that antimicrobial soap can detrimental through disrupting the balance of the skin microflora and irritating the skin. On this basis all the evidence would suggest that antimicrobial soap has no advantages over normal soap.

Myth: Busted

Myth 2: Warm or hot water is better for hand washing than cool water

The FDA have reviewed the recommended water temperature used for hand washing no less than three times. The results of the deliberations was that 110F (43°C) should be set as the recommended temperature in the belief a greater proportion of microbes can be removed. However, all the scientific evidence available suggests that water temperature has no effect on the removal of microbes in the range of 4 -49°C. However, other research in this area has illustrated that water temperature does influence the duration of hand washing with cold or hot water leading to shorter rinse times due to user discomfort.  

Myth: Busted

Myth 3: Paper towels are perform better than air dryers

The method used for drying hands following washing is one of the most contentious issues in the hand hygiene arena. The general thought pattern when devising the hand washing guidelines was that hands needed to be dried to prevent acquisition of contamination from surfaces. This is true to a degree but it should also be noted that hand drying can contribute significantly in reducing microbial levels on hands following washing.

The majority of papers published to date have been pro-paper towels and even the “The Myth Busters” returned the same conclusion. However, it should be noted that many of the comparative studies performed the researchers used hot air hand driers that generated a gentle breeze making the user resort to completing the drying process using ones pants. More modern high speed (air blades) driers certainly can dry hands to the same extent as paper towels within 20 seconds. When a comparison is made between air blades and paper towels there is no difference in terms of microbial log reduction or degree of hand dryness. Given that high speed hand driers are not universally available, the evidence would support the view that paper towels are indeed better that hot air driers.

Myth: True

So does it matter if hand washing protocols are not science based?

It is apparent that many aspects of the hand washing protocol are not based on hard scientific evidence but this does not mean it is the wrong thing to do. Still, by reconsidering if anti-microbial soap is really necessary then skin health could be improved. The savings on energy and water usage by reducing the recommended wash time and temperature could also have a positive impact. Regardless of this, we always need to consider the science when devising guidelines.

In the other corner we have Don Schaffner of Rutgers University (that’s in Jersey). Don writes that an Internet troll is defined by Wikipedia as “a person who sows discord on the Internet by starting arguments or upsetting people… with the deliberate intent of provoking readers into an emotional response…”. Doug knows the way to troll me is to send a link and ask me to blog about it (he really just wants to call me a troll).

An article from weau.com features the headline “Simple Sickness Prevention: Hand-Washing vs. Hand-Sanitizer”, and asks: what is more effective, old fashioned soap and water, or the alcohol based hand sanitizer?

Not a bad start. The story goes on to feature Doctor Jaime Marks, Assistant Professor of Medicine at UW-Health, who offers a variety of opinions on hand washing and hand sanitizer use.

Dr. Marks says it’s okay to use either hand-washing or hand-sanitizer.

Hmm. the FDA CFSAN Food Code 2–301.16(A)(3) would disagree, but I think I’m starting to like Dr. Marks…

If you notice your hands are soiled, you’ll want to wash your hands. Hand washing is at least 45–60 seconds, like singing through “Happy Birthday” twice in your head. With hand sanitizer, you’d want to use it for 20–30 seconds.

Whoops. That went off the rails quickly. Dr. Marks is certainly entitled to his opinion, but I’d like to see the scientific peer-reviewed basis for those statements. I’d waged they don’t exist. At least I’ve never seen them.

Dr. Marks continues…

Both are about equal as far as getting your hands clean as long as your hands are not soiled.

Hmmm. Dr. Marks wins me back. Sort of. In fact sometimes hand sanitizers even work when your hands are soiled.

The story concludes with some muddled statements about good bacteria and bad bacteria, building an immune response and getting a flu shot that don’t really hang together, but I’ll give Dr. Marks partial credit for trying. More credit next time if you cite the literature.

Or, according to The Smashing Pumpkins, “Emptiness is loneliness and loneliness is cleanliness and cleanliness is godliness and god is empty, just like me.”

Nosestretcher alert: no studies showing impact of diseases spread to customers from animals in petting zoo, but NY requires handwashing anyway

New York now requires petting zoos to provide for hand washing.

The new law says establishments providing an area where animals are grouped so visitors can view, touch or fondle them must provide appropriate facilities for washing.

claudia.e.coli.petting.zoo.may.14They should be located either at the exit of the petting area or within 50 feet. Signs are required.

The law also authorizes state and city health officials to formulate rules against the spread of bacteria and viruses carried by animals displayed at carnivals, fairs and amusement parks.

Sponsors say there have been no studies so far showing the impact of diseases spread to customers from animals in petting zoos.

And people wonder why journalism sucks.

A table of petting zoo outbreaks is available at http://barfblog.com/wp-content/uploads/2014/04/Petting-Zoo-Outbreaks-Table-4-8-14.xlsx.

Best practices for planning events encouraging human-animal interactions

Zoonoses and Public Health

G. Erdozain , K. KuKanich , B. Chapman  and D. Powell

http://onlinelibrary.wiley.com/doi/10.1111/zph.12117/abstract?deniedAccess

Educational events encouraging human–animal interaction include the risk of zoonotic disease transmission. It is estimated that 14% of all disease in the US caused by Campylobacter spp., Cryptosporidium spp., Shiga toxin-producing Escherichia coli (STEC) O157, non-O157 STECs, Listeria monocytogenes, nontyphoidal Salmonella enterica and Yersinia enterocolitica were attributable to animal contact. This article reviews best practices for organizing events where human–animal interactions are encouraged, with the objective of lowering the risk of zoonotic disease transmission.

Chipotle still sucks at food safety

A Chipotle restaurant in Gwinnett County, Georgia, has failed its health inspection.

chipotle_ad_2The restaurant, located at 860 Macon Highway in Lawrenceville, scored 60 out of 100.

The Gwinnett County health inspector noted that employees handling food at the restaurant were not washing their hands frequently enough to prevent contamination of food.

Other violations included:

  • Chicken not cooked to an internal temperature of 165 degrees Fahrenheit or above
  • Dining counters and tables not cleaned and sanitized by correct methods
  • Held potentially hazardous foods not maintained below 41 degrees Fahrenheit

Channel 2’s Carol Sbarge visited the packed restaurant where one customer said he wouldn’t have come if he knew the score.

“It’s very upsetting. I didn’t go to another restaurant because they had a low score. Now that I know that they had that 60, I’m (not) even going to come here. I had no idea,” said customer Steve Sessa.

The restaurant was still posting an old score of 90, which is a violation. 

http://www.wsbtv.com/videos/news/gwinnett-chipotle-fails-health-inspection/vCtD5K/

Schaffner: handwashing is an incomplete science, but we’re working on it

Friend of the blog Don Schaffner of Rutgers University tells the Academic Minute (in a quite professorial tone) that washing keeps bacteria and other pathogens at bay and all research suggests that keeping clean is a good thing, but handwashing is an inexact process.

Don-Schaffner-214x300Dr. Donald W. Schaffner is Extension Specialist in Food Science and Distinguished Professor at Rutgers University. Dr. Schaffner has authored more than 100 peer-reviewed publications, book chapters and abstracts. Dr. Schaffner has educated thousands of Food Industry professionals through numerous short courses and workshops in the United States and more than a dozen countries around the world. Dr. Schaffner was elected a Fellow of the IFT in 2010 and AAM in 2013 and is an Editor for the ASM journal Applied and Environmental Microbiology. Dr. Schaffner is the president of the IAFP 2013-2014.

You’ve probably heard all of your life that hand washing is important to public health.

In fact, the published research supports this quite strongly. Numerous scientific research articles show the positive impact on a variety of target populations when hand washing is encouraged, or in developing countries when something as simple as a bar of soap is provided to people that could not previously afford it.

You may have even heard advice about washing your hands: Things like “wash your hands for 20 seconds”, or you may have heard the same phrase, with 15 seconds or 30 seconds being the recommended time frame. The United States Centers for Disease Control and Prevention (the CDC) recommends teaching your child to wash their hands for as long as it takes to sing the “happy birthday” song twice (approximately 20 seconds).

You might be surprised to learn however, that the scientific basis for 5, 10, 15, 20, or even 30 seconds is virtually nonexistent. Research is currently underway in our lab to better characterize the effect of wash time, as well as other parameters on the effectiveness of a good hand wash. We are quantifying the effect of soap versus no soap, antibacterial versus plain soap, the effect of water temperature, the optimum wash time, and the method of drying.

 So, wash your hands! Especially after handling raw meat, changing a dirty diaper, or after you poop. How long should you wash your hands?

We’re working on it.

Should kids be allowed to wash hands at school? Or is sanitizer enough?

Someone wrote me this morning and said at their U.S. elementary school, the 5th graders are not permitted to wash hands after mandatory bathroom times and the teacher stands outside of the bathroom with hand sanitizer squirting it as each child leaves the bathroom. The hand dryers are too loud and the teachers don’t want wet hands because there’s no paper towel.

jon.stewart.handwashing.2002This as UN deputy secretary general, Jan Eliasson, warned the world’s lack of progress in building toilets and ending open defecation is having a “staggering” effect on the health, safety, education, prosperity and dignity of 2.5 billion people.

They may not be related, but proper sanitation requires access to proper tools.

In Denmark, nearly one-quarter of foodborne illness outbreaks from 2005 to 2011 were caused by asymptomatic food handlers, according to researchers from the Statens Serum Institut in Copenhagen.

“Symptoms compatible with norovirus infection among household members, especially children, of food handlers should be taken into account, as mechanical transfer of virus particles from private homes to industrial kitchens appears to be an important cause of outbreaks,” the researchers wrote in The Journal of Infectious Diseases. “Existing guidelines recommend exclusion of symptomatic and post-symptomatic food handlers and strict hand hygiene, when household members are ill with gastroenteritis.”

handwashing.junk.apr.13A study in Finland concluded Noroviruses are easily transferred to ready-to-eat foods via foodservice workers’ handling.

Researchers at the Finnish Food Safety Authority and the University of Helsinki confirm virus-free food ingredients and good hand hygiene are needed to prevent contamination of prepared foods.

Promote hand hygiene, but the tools have to be there.

Better hygiene through humiliation?

I’ve always been a fan of shame and blame, humility and hubris, carrots and sticks.

People can be complicated.

leadAccording to The Atlantic, a number of companies have designed systems that aim to nudge doctors and nurses into washing their hands regularly. One of these devices, a badge made by Biovigil, aims to exploit a very powerful emotion: shame.

When a doctor enters an exam room, the badge chirps and a light on it turns yellow—a reminder to the doctor as well as an alert to the patient that he is about to be touched by someone with unclean hands. If the doctor doesn’t wash her hands, the light flashes red and the badge makes a disapproving noise. After the doctor waves a freshly sanitized hand in front of the badge, alcohol vapors trigger a sensor that changes the light from red to green. Other systems include HyGreen, which also uses badges; Hyginex, a wristband that can tell when a user dispenses hand sanitizer (and vibrates if he or she doesn’t); and SwipeSense, which includes a hand-sanitizer dispenser that clips onto scrubs.

Each of these devices generates a log that’s uploaded to a database of what HyGreen calls “all hand hygiene events in the hospital”—a rundown of who’s washing up, and who isn’t. The data could help hospitals engage in after-the-fact analysis of how an outbreak occurred, and, with any luck, might help them to prevent the next one.

Handwashing is never enough: Minnesota paper says require handwashing stations at petting zoos

I was talking to my friend John this morning at my church – the ice arena – while the women were skating.

amy.hubbell.skates.jul.13 We talked about getting out of the rat race, and how it was nice we had wives to sorta support us, and he mentioned he was going to the Ekka today, and I said, beware the petting zoo, and got the usual response of, I never heard there was a risk.

As the Post Bulletin in Minnesota writes, every summer, there’s an E. coli outbreak originating from a traveling petting zoo, with the latest occurring at the Olmsted County Fair.

The report that at least 13 people, including three in Olmsted County, have been sickened by Escherichia coli O157:H7 after visiting the Zerebko Zoo Tran exhibit is a reminder that even healthy, well-cared-for animals can be vectors for disease.

The Minnesota Department of Health encourages the installation of hand-washing stations near animal exhibits and the display of posters on hand-washing. Some county fairs and festivals voluntarily comply, but we believe it should go a step further and make it a legal requirement to post signs and hand-washing stations at all livestock exhibits.

Kirk Smith, an epidemiology program manager with the state Health Department, said guidelines are sent to county fair and festival managers every year, but compliance is “modest to poor, so it’s really a frustrating issue for us.”

Five percent to 10 percent of children who get infected go on to develop severe complications, said Smith, pointing an 2012 outbreak in North Carolina, where a child died of an E. coli infection after visiting a county fair.

“If parents understand that there’s any appreciable risk from a bug that can cause kidney failure that’s fatal in 5 percent of the cases, they’ll manage that risk a lot better,” Smith said.

Best practices for planning events encouraging human-animal interactions

Zoonoses and Public Health

G. Erdozain , K. KuKanich , B. Chapman  and D. Powell

http://onlinelibrary.wiley.com/doi/10.1111/zph.12117/abstract?deniedAccess

Educational events encouraging human–animal interaction include the risk of zoonotic disease transmission. It is estimated that 14% of all disease in the US caused by Campylobacter spp., Cryptosporidium spp., Shiga toxin-producing Escherichia coli (STEC) O157, non-O157 STECs, Listeria monocytogenes, nontyphoidal Salmonella enterica and Yersinia enterocolitica were attributable to animal contact. This article reviews best practices for organizing events where human–animal interactions are encouraged, with the objective of lowering the risk of zoonotic disease transmission.

A table of petting zoo outbreaks is available at http://barfblog.com/wp-content/uploads/2014/04/Petting-Zoo-Outbreaks-Table-4-8-14.xlsx.

Petting zoos can suck: Second outbreak of infection with a rare Cryptosporidium parvum genotype in schoolchildren associated with contact with lambs/goat kids in Norway

In March 2012, a second outbreak of Cryptosporidium parvum affected children following a stay at a holiday farm in Norway; the first outbreak occurred in 2009. We studied a cohort of 145 schoolchildren who had visited the farm, of which 40 (28%) were cases.

petting zoo 1Cryptosporidium oocysts were detected in faecal samples from humans, goat kids and lambs. Molecular studies revealed C. parvum subtype IIa A19G1R1 in all samples including human samples from the 2009 outbreak. A dose–response relationship was found between the number of optional sessions with animals and illness, increasing from two sessions [risk ratio (RR) 2·7, 95% confidence interval (CI) 0·6–11·5] to six sessions (RR 8·0, 95% CI 1·7–37·7). The occurrence of two outbreaks 3 years apart, with the same subtype of C. parvum, suggests that the parasite is established in the farm’s environment. We recommend greater emphasis on hand hygiene and routines related to animal contact.

Best practices for planning events encouraging human-animal interactions

Zoonoses and Public Health

G. Erdozain , K. KuKanich , B. Chapman  and D. Powell

http://onlinelibrary.wiley.com/doi/10.1111/zph.12117/abstract?deniedAccess

Educational events encouraging human–animal interaction include the risk of zoonotic disease transmission. It is estimated that 14% of all disease in the US caused by Campylobacter spp., Cryptosporidium spp., Shiga toxin-producing Escherichia coli (STEC) O157, non-O157 STECs, Listeria monocytogenes, nontyphoidal Salmonella enterica and Yersinia enterocolitica were attributable to animal contact. This article reviews best practices for organizing events where human–animal interactions are encouraged, with the objective of lowering the risk of zoonotic disease transmission.

A table of petting zoo outbreaks is available at http://barfblog.com/wp-content/uploads/2014/04/Petting-Zoo-Outbreaks-Table-4-8-14.xlsx.

 

Sanitizers or handwashing? Or both?

Installing alcohol-based hand sanitizer dispensers in classrooms may not mean fewer sick days for kids, a New Zealand study has suggested.

genitals.hand.sanitizerThe study, published today in the journal PLOS Medicine, found absence rates at schools that installed dispensers in classrooms as part of the survey were similar at those “control” schools which did not.

The research, led by Associate Professor Patricia Priest and University of Otago colleagues, involved 68 schools in Christchurch, Dunedin and Invercargill and nearly 2,500 pupils.

In schools randomly assigned to the “intervention” group, alcohol-based hand sanitizer dispensers were installed in the classrooms over two winter terms and the children were asked to use the dispensers after coughing or sneezing and on the way out of the classroom for breaks.

Dr Priest emphasizes that the study’s findings were not relevant to the importance of hand hygiene in general, nor did it change the message of cleaning hands before eating or after using the toilet, coughing or touching pets.

In a related story, the USA Today reports that alcohol-based hand sanitizers are better at killing germs and that soap and water is generally the best option but, hand sanitizers come in handy when you aren’t close to a sink.

Fist bumps are less germy than handshakes

I went to the Apple store in Brisbane to fix my iPhone and got a lot of handshakes.

Then I watched staff shake a lot of other hands.

Wonder_Twins-fist-bumpI was a dumbass.

So says science.

“A short, sweet fist bump will transmit the least bacteria,” and even a high-five is better than a traditional shake, says David Whitworth, a senior lecturer in biochemistry at Aberystwyth University-Ceredigion in the United Kingdom.

Whitworth and a colleague systematically tested the three greetings for a study published Monday in the American Journal of Infection Control.

For the experiment, one of them repeatedly dipped a gloved hand into a container loaded with a not-too-dangerous strain of E. coli bacteria. The dirty-gloved scientist let the film dry, then shook, fist-bumped or high-fived the other person’s clean, gloved hand. Finally, the receiving gloves were tested for bacteria.

Result: The shakes transmitted about 10 times more bacteria than the fist bumps and about two times more than the high fives. The longest, firmest shakes transmitted the most.

In a separate round in which the gloves were dipped in paint rather than bacteria, the researchers found one rather obvious explanation: Bigger areas of the hands touched during the shakes. Handshakes also tended to last longer, but the researchers found more clinging germs even when they compared shakes to fist bumps and high-fives of the same duration.

Whitworth’s findings “are not surprising,” says Mary Lou Manning, an associate professor in the school of nursing at Thomas Jefferson University in Philadelphia and president-elect of the Association for Professionals in Infection Control and Epidemiology.

She is not enthusiastic about replacing handshakes with fist bumps in hospitals. The better, more hygienic idea, she says, is to promote rigorous hand-washing and ban hand-to-hand greetings altogether. “That’s already starting to happen” in a lot of places, she says.