It’s all in the friction: Hand dryers are germ-flinging BS

The benefits of paper towels versos conventional blow dryers for drying after handwashing are well-documented.

handwash_south_park(2)But what about those high-tech – and expensive – Dyson thingies that seem to be popping up everywhere.

I say, show me the data.

Caroline Weinberg writes that a study published in the Journal of Applied Microbiology showed that Dyson jet air dryers can fling germs as far as 10 feet from the device.

For the experiment, researchers dipped their gloved hands in a suspension of the bacteriophage MS2 (similar in structure to the contagious enteric viruses transmitted in poop). The hands were then dried by one of three methods. First up were Dyson jet air dryers, which are designed to push water off of your hands in 10 seconds with roughly the force of a jet engine. Next were warm air dryers, which blow warm air downwards and supposedly remove water via evaporation. The final competitor was paper towels, which use absorbent paper to remove water from your hands (and actually leave them dry).

The first part of the experiment looked at how many bacteria are blown back on you during the drying process. Researchers erected a vertical board roughly 16 inches away from each dryer and counted the viral particles that landed on it. Overall, the jet dryer dispersed 60 times more particles than the warm air dryer and 1,300 more than the paper towel. 70 percent of particles hit the board between 2.5 and 4.5 feet—roughly chest or stomach level on an woman of average height, or right at the face level of a small child. At the highest density point, the jet air dryer dispersed 167 times as many viral particles as the warm air dryer and 8,340 times as many as a paper towel.

dyson.air-blade-thumb-468x369-147704For the second part of the experiment, researchers studied air dispersal, or how much of the bacteria is spread into the air around the machine or towel. Airborne virus counts were consistently higher around the jet dryer both over time and distance. The jet dryer dryer propelled the virus as far as 10 feet away, with high levels recorded a full 15 minutes after use. There was no significant difference in air dispersal between warm air dryers and paper towels.

This isn’t a perfect study: Because it was done in a lab setting, researchers could not account for individual behaviors or real world differences. They also only tested one example of each hand drying device (Dyson is taking the heat here, but they are not the only makers of jet air dryers) and did so over a small number of trials. Critics of the study also rightfully point out that most people don’t dip their hands in bacteria prior to using the hand dryers: they wash their hands first. And it’s true that if one were to stick perfectly clean hands into a dryer, there would not be germs to blow around.

Unfortunately, here in the real world, 95% of people using public restrooms fail to adequately wash their hands. Sure, a small percentage may use the scientifically vetted, 42-second-long, six-step hand washing process that most effectively rids your hands of all the filthy germs you’ve picked up in the bathroom and world at large. The rest of them (OK, us) are doing a quick scrub or, worse, simply passing their hands under a running faucet for a few seconds for the illusion of cleanliness. So while the hands most people place in the dryer aren’t drenched in germs, they are likely carrying, among other things, poop particles. Poop particles that the machine then proceeds to blow all over the room, including back on the very hands you just cleaned.

handwashing.blow.dryer.09This isn’t the first time a study has suggested that hand dryers are germ cannons, either. A 2014 study published in the Journal of Hospital Infection also supports this finding—but it was dismissed by Dyson as funded by Big Paper Towel (in their defense, that study was literally funded by Big Paper Towel, i.e. the European Tissue Symposium,). Dyson would direct us, instead, to 2011 study published in the Journal of Applied Microbiology that found their air dryers to be more effective at preventing the spread of germs than warm air dryers. Now it was Big Paper Towel’s turn to cry foul—that study was funded by Dyson Limited. The current study in question is funded independently by the researchers’ university (though the lead author has worked with the European Tissue Symposium in the past) lending it a hopefully uncontaminated air of legitimacy.

A few months ago, shortly after this study was published, Dyson posted an ominously narrated attack ad of sorts titled “Paper’s Dirty Secret.” Don’t listen to Big Jet Dryer’s propaganda (well, maybe listen to it, because the video is hilarious—but don’t believe it). It is true that a 2012 pilot study found unused paper towels to be contaminated with small amounts of bacteria. But paper towels have been repeatedly shown to be efficient, effective, and—perhaps most importantly—not responsible for flinging extra poop germs through the air.

 

Going public: 167 people with the runs in Iowa

That moment happened.

Usually it takes until puberty, but it happened.

diarrhea.toiletMy 7-year-old daughter, who was in a local Dettol commercial, which I had nothing to do with (that’s her, at the end, second row from the bottom, far rightin the pic below; I’ve always shamelessly promoted my children).

Yet this morning, she was too embarrassed to answer what number 1 meant, and number 2, while watching some other video this morning before school, something about poop.

And it happened.

Sure, kids find me hilarious until about 11-years-old, then it’s embarrassment for 10 years, then they come around.

Maybe the folks in Dubuque County, Iowa feel the same way, maybe they have state laws limiting what they can say.

But when 167 people have diarrhea since Oct 1, public health has to step in (not in the #2).

Seriously, no public announcement until April 11, 2011, on an outbreak that started Oct. 1, 2015?

 “This is a high number of diagnosed cases that we have had,” said Patrice Lambert, executive director of the Dubuque County Health Department.

Shigellosis is a disease caused by the bacterium shigella, which causes watery and sometimes bloody diarrhea, according to Lambert.

 “Wash your hands with soap and water,” Lambert said. “That’s the easiest thing to do, not only for shigellosis but for all communicable diseases.

Handwashing is never enough.

 

Medium and message: Need to frequently change handwashing signs to be effective

I’m a food safety voyeur.

Supermarkets, farmers markets, restaurants – fancy or not – kitchens, farms, I’ve been professionally watching people for 20 years.

surprise-01Chapman likes to recount how he was invited to the GFSI Consumer Goods Forum as a last minute replacement speaker in 2013 to talk about food safety infosheets and how we evaluated them.  He said that the literature shows surprise matters when it comes to communicating risks – and a message that is up all the time, like a hand washing sign, probably doesn’t do much after the day it was posted (when it is surprising to the food handler).

The level of surprise in a message determines how successfully the information is received. In 1948, the Bell Telephone Company commissioned a study on communication as a mathematical theory to aid in the design of telephones.  In a study of brain function, Zaghloul and colleagues (2009) also showed the brain’s sensitivity to unexpected or surprising information plays a fundamental role in the learning and adoption of new behaviors.

During the Q&A session at the end of the session someone from a German retail store asked Chapman if he was suggesting that that they take down all the handwashing posters they had up, and Chapman said, yes, unless they plan on changing them every couple of days. The audience had an audible gasp.

We’ve found that posting graphical, concise food safety stories in the back kitchens of restaurants can help reduce dangerous food safety practices and create a workplace culture that values safe food.

It was the first time that a communication intervention such as food safety information sheets had been validated to work using direct video observation in eight commercial restaurant kitchens and was published in the  Journal of Food Protection.

hand_sanitizer_hospital_11We found that infosheets decreased cross-contamination events by 20 per cent, and increased handwashing attempts by 7 per cent.

Based on observations of more than 5,000 patrons at a hospital-based cafeteria, we showed that an evidence-based informational poster can increase attempts at hand hygiene.

So we gladly welcome new work on food safety messages and media in poultry processing facilities.

Signs can provide repetitive training on specific food safety practices for multicultural food processing employees. Posted signs for workers in many food processing facilities tend to be text-heavy and focus specifically on occupational hazard safety. The purpose of this study was to evaluate the effectiveness of newly-developed hand washing pictograms on employees’ hand washing behavior using video observation.

Five employee hand washing behaviors (soap use, wash completeness, wash time, complete rinsing, and towel use) were evaluated with (a) no intervention, company signs posted and considered the baseline; and compared to (b) hand washing behavior the next day (short term) and two weeks (long term) after experimental hand washing signs were displayed at a raw poultry slaughter facility (Facility A) and a poultry further processing facility (Facility B).

sponge.bob.handwashingBoth facilities showed a significant increase (p < 0.05) in soap use after the new sign was introduced at both short and long term time periods. There was a significant increase (p < 0.05) in washing, time of washing, and rinsing observed by Facility B employees, when baseline data was compared to the short term. This indicates that a new sign could increase hand washing compliance at least in the short term. Sign color also had a significant effect (p < 0.05) on employee behavior for washing and time of washing. Behavior for four of the five variables (soap, wash, time of wash, and towel use) was significantly different (p < 0.05) between baseline and either experimental observation period.

While signs can be a useful tool to offer as recurring food safety training for food processing employees, employees tend to revert back to old habits after several weeks.

Evaluation of how different signs affect poultry processing employees’ hand washing practices

Food Control, Volume 68, October 2016, Pages 1–6

Matthew Schroeder, Lily Yang, Joseph Eifert, Renee Boyer, Melissa Chase, Sergio Nieto-Montenegro

http://www.sciencedirect.com/science/article/pii/S0956713516301244

 

Nebraska health board recommends no bare hands for restaurants

The No. 1 cause of what people often call food poisoning is not spoiled food. It is a flu-like illness called norovirus that comes with diarrhea and vomiting.

handwash_south_park(2)And the No. 1 cause of norovirus is people who have the virus on their hands touching food without gloves.

To help prevent outbreaks of the virus, a health-related advisory group to the Lincoln-Lancaster County Health Department has recommended the city tighten restaurant rules, seriously limiting when staff can touch ready-to-serve food with their bare hands.

The City Council likely will hold a public hearing on the no-bare-hands policy April 11. The Health Department advisory board approved it in early March. 

The idea behind the policy is that once food is cooked, no staffer should touch it before a customer eats it, said Scott Holmes, manager of the Environmental Health Division with the local health department. 

The proposed rule does allow some exceptions.

Staff can touch ready-to-eat food before it’s cooked, garnish beverages and wash fruits and vegetables with bare hands.

Some eating establishments already follow a no-bare-hands policy, including those that serve vulnerable or high-risk populations — people in custodial care, assisted-living facilities, hospitals, nursing homes and senior centers, for example.

And many chain restaurants already have such policies, Holmes said.

The local proposal follows a national model, with some exceptions. The committee that developed the Lincoln policy eliminated a few of the rules, ones that created the most controversy in other communities.

They said loads: reducing cross-contamination via hands

Hand washing and glove use are the main methods for reducing bacterial cross-contamination from hands to ready-to-eat food in a food service setting. However, bacterial transfer from hands to gloves is poorly understood, as is the effect of different durations of soap rubbing on bacterial reduction.

handwashing.loadsTo assess bacterial transfer from hands to gloves and to compare bacterial transfer rates to food after different soap washing times and glove use, participants’ hands were artificially contaminated with Enterobacter aerogenes B199A at ∼9 log CFU. Different soap rubbing times (0, 3, and 20 s), glove use, and tomato dicing activities followed. The bacterial counts in diced tomatoes and on participants’ hands and gloves were then analyzed.

Different soap rubbing times did not significantly change the amount of bacteria recovered from participants’ hands. Dicing tomatoes with bare hands after 20 s of soap rubbing transferred significantly less bacteria (P < 0.01) to tomatoes than did dicing with bare hands after 0 s of soap rubbing. Wearing gloves while dicing greatly reduced the incidence of contaminated tomato samples compared with dicing with bare hands. Increasing soap washing time decreased the incidence of bacteria recovered from outside glove surfaces (P < 0.05).

These results highlight that both glove use and adequate hand washing are necessary to reduce bacterial cross-contamination in food service environments.

Adequate hand washing and glove use are necessary to reduce cross-contamination from hands with high bacterial loads

Journal of Food Protection®, Number 2, February 2016, pp. 184-344, pp. 304-308(5)

Robinson, Andrew L.; Lee, Hyun Jung; Kwon, Junehee; Todd, Ewen; Rodriguez, Fernando Perez; Ryu, Dojin

http://www.ingentaconnect.com/content/iafp/jfp/2016/00000079/00000002/art00016

Does your state suck at food safety? CDC releases prevention status reports

CDC has just released the latest Prevention Status Reports (PSRs), which highlight the status of state-level policies and practices to prevent or reduce problems affecting public health. The PSRs cover 10 public health topics—including food safety—and rate states on their implementation of recommended policies and practices. 

 

skippy.burger skippy.burgerThe reports include a new measure on state adoption of selected provisions in the 2013 Food and Drug Administration (FDA) Food Code. The Food Code is a science-based model code that states can use to develop or update their food safety rules to better prevent foodborne illness and outbreaks.

CDC identified four Food Code provisions especially important in reducing outbreaks in restaurants and other retail food establishments:

  • exclude ill food service staff from working until at least 24 hours after symptoms, such as vomiting and diarrhea, have ended;
  • prohibit bare hand contact with ready-to-eat food;
  • require at least one employee in a food service establishment to be a certified food protection manager; and,
  • require food service employees to wash their hands.

The other two measures continue from the 2013 Prevention Status Reports. High scores for these two measures enable efficient detection and investigation of outbreaks:

  • speed of DNA fingerprinting using pulsed-field gel electrophoresis (PFGE) testing for all reported cases of Shiga toxin-producing E. coli O157; and,
  • completeness of PFGE testing of Salmonella.

The PSR website has been enhanced to include an interactive map that leads directly to topic reports for each state. The website also includes State Summary tables that outline the full set of policy and practice ratings for each state; a National Summary that gives aggregate ratings across states and rating comparisons for 2013 and 2015; the PSR Quick Start Guide; a fact sheet; answers to frequently asked questions; and a link to the 2013 PSRs. 

Australian bakery owner slams ‘ridiculous’ food safety fine for paper towel slip

Someone who’s not a fan of restaurant inspections is Matthew Carr, the owner of the Corner Bakehouse and Café in Budgewoi, who was fined $880 for not having enough paper towels­.

BudgewoiCarr has slammed the penalty as “ridiculous” after his bakery was one of 16 Wyong Shire eateries named and shamed on a statewide food safety register.

Carr was forced to stump up $1760 in two fines last year for noncompliance in relation to cleaning requirements with details published on the NSW Food Authority register and reported in the ­Express Advocate.

 “What this guy found was insignificant — silly things like paper towels,” he said.

“I think it is obviously just revenue-raising for Wyong Council and these people are being sent to nail businesses left, right and centre.”

Noro goes to school

Norovirus is striking university campuses throughout the U.S.

back.to.schoolA reported norovirus outbreak at the University of Michigan created some scheduling rearrangements for the 2016 Big Ten Women’s Swimming and Diving Championships, according to a report by Swimming World Magazine.

In 2010, the NCAA Men’s Swimming and Diving Championships were postponed a day to allow decontamination of the pool at the McCorkle Aquatic Pavilion in Columbus, Ohio after a similar norovirus outbreak.

The cause of a stomach illness that swept through Ursinus College in Pennsylvania over the past week has been identified.

School officials say Norovirus has been confirmed with at least 214 students, faculty and staff reporting symptoms — almost 13 per cent of current enrollment.

And a mystery illness hit a Kansas City volleyball team while they were visiting Omaha to attend a tournament.

For months the team, Club North, prepared for a huge tournament at the Century Link. It’s an opportunity to play in front of college recruiters and stand out as a top player, but for some girls on the team, this past weekend was a nightmare.

Stacey McBride said her daughter and three other girls became violently ill on Monday.

“How four healthy girls get sickened and incubated at the very same time where they all got up at 4 o’clock in the morning violent vomiting. I’d like to know, how did that happen?” said McBride. “They were crippled down on the floor. They didn’t think that they could play without throwing up so there was no reason to play.”

Tennessee restaurant manager ‘unaware’ of food safety requirements

A series of food safety violations were found at a breakfast and lunch cafe in North Knoxville and that includes one violation we’ve never seen before.

Rami’s CafeThe inspector spent quite a long time, according to her report, checking this restaurant mainly because there were so many different violations and quite a lot of discussion went on with the manager.

Rami’s Cafe, 3553 N. Broadway – Grade: 74

While the grade of 74 is passing, a re-inspection is required within a week or so.

The inspector reports food temperatures were off. Chili was found at 120 degrees and mashed potatoes were at 105 degrees, but 135 degrees and above is the required temperature to slow the growth of bacteria which is the leading cause of food borne illness. The inspector ordered the mashed potatoes thrown out.

The inspector writes that she found a soiled rag on top of the grill were food is prepared. She also found cooked bacon that was ready to be served, on top of a soiled rag.

The inspector writes that she watched the cook place raw hamburgers on the grill then began touching several utensils without washing his hands first. While preparing a sandwich, the cook also touched a ready-to-ear sandwich with his bare hands without washing his hands first.

The inspector writes there was “no managerial control.” WATE 6 On Your Side has not seen this violation in a health report before.

As part of the process during each inspection, restaurant managers are asked questions about how to manage risk factors. In her report the inspector writes, the manager at Rami’s was “unaware” of food safety requirements. She recommended that the manager attend the county’s free food safety class held every month.

They said loads: Handwashing and glove use both necessary

Handwashing and glove use are the main methods for reducing bacterial cross-contamination from hands to ready-to-eat food in a food service setting.

amy.sorenne.handwashingHowever, bacterial transfer from hands to gloves is poorly understood, as is the effect of different durations of soap rubbing on bacterial reduction. To assess bacterial transfer from hands to gloves and to compare bacterial transfer rates to food after different soap washing times and glove use, participants’ hands were artificially contaminated with Enterobacter aerogenes B199A at ∼9 log CFU. Different soap rubbing times (0, 3, and 20 s), glove use, and tomato dicing activities followed. The bacterial counts in diced tomatoes and on participants’ hands and gloves were then analyzed. Different soap rubbing times did not significantly change the amount of bacteria recovered from participants’ hands.

Dicing tomatoes with bare hands after 20 s of soap rubbing transferred significantly less bacteria (P < 0.01) to tomatoes than did dicing with bare hands after 0 s of soap rubbing. Wearing gloves while dicing greatly reduced the incidence of contaminated tomato samples compared with dicing with bare hands. Increasing soap washing time decreased the incidence of bacteria recovered from outside glove surfaces (P < 0.05).

These results highlight that both glove use and adequate hand washing are necessary to reduce bacterial cross-contamination in food service environments.

Adequate hand washing and glove use are necessary to reduce cross-contamination from hands with high bacterial loads.

J Food Prot. 2016 Feb; 79(2):304-8. doi: 10.4315/0362-028X.JFP-15-342.

Robinson AL, Lee HJ, Kwon J, Todd E, Rodriguez FP, Ryu D

http://www.ncbi.nlm.nih.gov/pubmed/26818993