I’d largely forgotten about my lab’s handwashing phase, probably because I was leaving the safety (shurley not) of Kansas and heading to Australia.
But was reminded from this excerpt in The New Yorker from Nate Dern’s “Not Quite a Genius,” to be published by Simon & Schuster:
Employees must wash hands.
Employees must wash their own hands.
Employees must wash their own hands after they use the restroom.
Employees of this restaurant must wash their own hands after they use the restroom.
Employees of this restaurant must wash their own hands (literally, not metaphorically) after they use the restroom.
Employees of this restaurant must wash their own hands (literally, not metaphorically) after they use the restroom, or else they are in violation of the health code.
Employees of this restaurant must wash their own hands (literally, not metaphorically) after they use the restroom, or else they are in violation of the health code, and, no, there is no practical way to regulate or enforce this rule.
Employees of this restaurant must wash their own hands (literally, not metaphorically) after they use the restroom, or else they are in violation of the health code, and, no, there is no practical way to regulate or enforce this rule, but, yes, we still ask, and trust that you will comply.
Employees of this restaurant must wash their own hands (literally, not metaphorically) after they use the restroom, or else they are in violation of the health code, and, no, there is no practical way to regulate or enforce this rule, but, yes, we still ask, and trust that you will comply, and, O.K., we apologize for the condescending tone of the posting of this rule, which seems to imply that without such a sign we would assume that our employees are disgusting children with no regard for their own hygiene.
Employees must wash hands. Greg has been fired.
Filion, K., KuKanich, K.S., Chapman, B., Hardigree, M.K., and Powell, D.A. 2011. Observation-based evaluation of hand hygiene practices and the effects of an intervention at a public hospital cafeteria. American Journal of Infection Control 39(6): 464-470.
Hand hygiene is important before meals, especially in a hospital cafeteria where patrons may have had recent contact with infectious agents. Few interventions to improve hand hygiene have had measureable success. This study was designed to use a poster intervention to encourage hand hygiene among health care workers (HCWs) and hospital visitors (HVs) upon entry to a hospital cafeteria.
Over a 5-week period, a poster intervention with an accessible hand sanitizer unit was deployed to improve hand hygiene in a hospital cafeteria. The dependent variable observed was hand hygiene attempts. Study phases included a baseline, intervention, and follow-up phase, with each consisting of 3 randomized days of observation for 3 hours during lunch.
During the 27 hours of observation, 5,551 participants were observed, and overall hand hygiene frequency was 4.79%. Hygiene attempts occurred more frequently by HCWs than HVs (P = .0008) and females than males (P = .0281). Hygiene attempts occurred more frequently after poster introduction than baseline (P = .0050), and this improvement was because of an increase in frequency of HV hand hygiene rather than HCW hand hygiene.
The poster intervention tool with easily accessible hand sanitizer can improve overall hand hygiene performance in a US hospital cafeteria.
Wilson, S.M., Jacob, C.J. and Powell, D.A. 2011. Behavior-change interventions to improve hand hygiene practice: A review. Critical Public Health 21: 119-127.
Despite the role of hand hygiene in preventing infectious disease, compliance remains low. Education and training are often cited as essential to developing and maintaining hand-hygiene compliance, but generally have not produced sustained improvements. Consequently, this literature review was conducted to identify alternative interventions for compelling change in hand-hygiene behavior. Of those, interventions employing social pressures have demonstrated varying influence on an individual’s behavior, while interventions that focus on organizational culture have demonstrated positive results. However, recent research indicates that handwashing is a ritualized behavior mainly performed for self-protection. Therefore, interventions that provoke emotive sensations (e.g., discomfort, disgust) or use social marketing may be the most effective.
While I was grocery shopping one day at my regular store, I noticed that one of the doors to the dairy refrigerator case was missing. There was no sign or notice to explain the gaping hole where the door should have been in front of the shredded cheese, nor was any attempt made to compensate for the absent door, such as by relocating the items in that section or putting up a temporary covering.
After first being a bit confused when trying to reach for a non-existent handle, these questions popped into my head:
• how can the food in this section be at a safe temperature, as well as the foods on either side of it? and,
• doesn’t this missing door affect the ability of the case to maintain its temperature?
I’m a food safety nerd. Most people just want to shop and get on with whatever they are doing, but I’m subconsciously always looking for food safety behaviors. The person standing behind me was probably more interested in which brand was the least expensive or which package looked the freshest, or just wanted me to get out the way so they could buy their cheese and leave.
Does the lack of a door on a normally enclosed refrigerator case pose a food safety risk for dairy the products in that case? Depends on whom you ask. The average consumer (interpret this as you choose) often doesn’t see the same food safety risks when shopping in grocery stores compared to food safety folks.
Our group from North Carolina State teamed up with John Luchansky and Anna Porto-Fett at the U.S. Department of Agriculture’s Agricultural Research Service to investigate this difference between consumers and food safety folks in food safety risk perception when shopping at grocery stores. We conducted a national survey and several focus groups where, instead of just describing a situation, we showed pictures of a food safety situation someone could actually encounter while shopping. In addition to asking questions about whether each photo was safe or unsafe, we wanted to know about the actions, if any, people would take to do something about a situation they thought was unsafe. We prodded them further with questions about how their perceptions of safety would affect their shopping behaviors.
We found that consumers and food safety folks don’t always see the same food safety risks. There were some situations consumers perceived as risky but that weren’t actually risks, like seeing an insect on the floor. There were also some risks that food safety folks saw but consumers missed, like food not properly stored within the refrigerated area.
I was explaining our study to a friend the other day, and she flat out told me, “I look for food quality when I’m shopping – is it fresh, is there mold or signs of damage, does it look ok?” This is exactly what we found. Consumers are looking for those quality aspects, but aren’t always seeing the warning signs that the safety of the food could be at risk. The viruses, bacteria, and other things that cause foodborne illness such as Listeria monocytogenes, might be present on foods in the grocery store at high levels by not storing soft cheeses at the proper temperature, allowing bacteria to grow more quickly.
Our research team will be taking this one step further to better understand the mind of the shopper and see things through their eyes. Everyday consumers will become our secret shoppers, and we plan to arm them with the information they need to be food safety detectives every time they shop. #citizenscience for the win.
Katrina Levine, Mary Yavelak, John B. Luchansky, Anna C. S. Porto-Fett, and Benjamin Chapman
Journal of Food Protection
August 2017, Vol. 80, No. 8, pp. 1364-1377
To better understand how consumers perceive food safety risks in retail food store settings, a survey was administered to 1,041 nationally representative participants who evaluated possible food safety risks depicted in selected photographs and self-reported their perceptions, attitudes, and behaviors. Participants were shown 12 photographs taken at retail stores portraying either commonly perceived or actual food safety contributing factors, such as cross-contamination, product and equipment temperatures, worker hygiene, and/or store sanitation practices. Participants were then asked to specifically identify what they saw, comment as to whether what they saw was safe or unsafe, and articulate what actions they would take in response to these situations. In addition to the survey, focus groups were employed to supplement survey findings with qualitative data. Survey respondents identified risk factors for six of nine actual contributing factor photographs >50% of the time: poor produce storage sanitation (86%, n = 899), cross-contamination during meat slicing (72%, n = 750), bare-hand contact of ready-to-eat food in the deli area (67%, n = 698), separation of raw and ready-to-eat food in the seafood case (63%, n = 660), cross-contamination from serving utensils in the deli case (62%, n = 644), and incorrect product storage temperature (51%, n = 528). On a scale of 1 to 5, where 1 was very unsafe and 5 was very safe, a significant difference was found between average risk perception scores for photographs of actual contributing factors (score of ca. 2.5) and scores for photographs of perceived contributing factors (score of ca. 2.0). Themes from the focus groups supported the results of the survey and provided additional insight into consumer food safety risk perceptions. The results of this study inform communication interventions for consumers and retail food safety professionals aimed at improving hazard identification.
I didn’t know Don Schaffner, food safety guru and pop sensation at Rutgers University, was a Brittney Spears fan.
But he writes, whoops, I did it again, putting publication of peer-reviewed research ahead of press release.
We had an article published in the Journal Food of Protection earlier this week. While this current research is no five second rule, I thought it might garner some press interest, so I worked with colleagues at my university to put together a press release. I do enjoy talking to the media as part of my job, and it’s especially fun when it’s my own research.
(That’s why I became a professor, because I was bored talking about other people’s research and wanted to talk about my own — dp)
I thought I would take a little bit of time and share with barfblog.com readers about the process, because you folks are into this too.
An early draft of the press release had the title “Cool Water as Effective as Hot for Killing Germs”. This led to a conversation with my colleague in media relations who explained that using the word “killing” in the headline would lead to many more hits on Google (the modern-day equivalent of “if it bleeds, it leads”). I had to explain, that while I know all about search engine optimization (SEO), I could not in good conscience tell a scientific fib. Handwashing, for the most part does not kill germs, it simply removes them from your hands, and allows them to be washed down the drain.
Which brings me to antibacterial soaps – which seem to kill germs. This particular research article did look at the question of antibacterial soaps, and basically led to the same conclusion as our other on the issue: antibacterial soaps do work better than plain soaps when it comes to reducing bacterial counts on the hands, probably because there is some actual bacterial killing going on. For a variety of reasons, antibacterial soaps tend to work people up into a lather (pun intended… who says scientists have to be serious?). I had one journalist tell me [no link for you, sleazy British Tabloid] that they had already come to the conclusion that antibacterial soaps don’t work, and could I just say that. No, I explained I could not just say that, because that’s not what our research found. Instead, we found a highly significant difference (p= 0.0003) between hand washes with an antibacterial soap, and with a similarly formulated plain soap. In this particular study the difference was small, about 0.3 log. I know many readers of this blog are comfortable and thinking on the log scale, but for you non-microbiologists, 0.3 log corresponds to about a 50% greater reduction. Now 50% sounds like a lot to a non-microbiologist, but when you’re doing food microbiology, sometimes the data themselves can vary by 0.5 logs, or almost 70%. So what we ended up saying in the manuscript was, while highly significant, the difference was “within the range of error for microbiological data (i.e., a clinically insignificant difference).” I wish I’d said that a bit more forcefully in the manuscript, but sometimes we have to make compromises in peer review. The bottom line? I believe that antibacterial soap works better than plain soap in reducing bacteria on your hands. We reach this conclusion in our meta-analysis on the subject, and even this relatively small difference can have a profound effect on public health, at least if you believe our risk assessment manuscript on the subject.
I wanted to stress in the press release, and what I’ve been leading with during my media interviews, is that wash water temperature makes no difference, at least in the range that we studied (~ 60°F to 100°F). Our data show that there was no significant difference, no matter what temperature was used in the hand wash. Water temperature has along an interesting history in the FDA model food code. It used to be that the code specified a specific water temperature for washing the hands. It turns out that that temperature was based on the temperature at which bacon grease liquefies. The current code says that hands must be washed in warm water. Elsewhere in the current code it specifies that a hand wash sink must be capable of dispensing water at 100°F, hence our reason for doing the research. One point that I’ve been stressing in the media interviews is that it’s all about comfort. We want people to be comfortable when their washing their hands, and so my advice is use whatever water is most comfortable for you. It remains to be seen whether we will be able to change what’s in the code. Check back in 2018 after the next Conference for Food Protection
We looked at several other factors in this research as well. We investigated the volume of soap used: 0.5 mL, one mL and two mL, and we found no difference between these volumes of soap. Of course this doesn’t mean you can use as little soap as you want, my recommendation is to use at least 0.5 mL. Using more than this doesn’t seem to make a difference. This is also consistent with what we found in our [meta-analysis](https://www.ncbi.nlm.nih.gov/pubmed/22054188).
In a recent paper published in Food Protection Trends, my PhD student Dane Jensen (who was also the lead author on this handwashing study), and I published an analysis of recommendations on handwashing signs. Dane had a hand (pun intended, see above) in several of the handwashing research manuscripts coming out of my lab in recent years. What we found in the FPT handwashing signage research was that handwashing recommendations were all over the place. So we decided to study lather time in this current manuscript. For purposes of our research we defined lather time as the time from when the soap is applied, until the water rinse begins. We studied five, 10, 20, and 40 second lather times. We only saw a statistically significant difference between lather times of five and 20 seconds. The recommendation I would draw from this finding, is to lather for at least 10 seconds. Lathering for more than 10 seconds does not appear to offer any additional benefit.
One of the questions that seems to come up again and again in media interviews on this topic is “who funded the research”. While I understand the motivation for the question, it’s starting to get under my skin (okay okay, I’ll stop with the puns). The question seems to imply that somehow if I take money from the industry, my results are not to be trusted. I strongly resent the implication. It’s damn difficult to get grants these days, and I don’t think it’s going to get any easier until something changes in Washington. We funded this research using discretionary money, but I’m proud that we did it in collaboration with our co-authors from GOJO. They were instrumental in helping us think about our experimental design, plus they gave us free soap. They are also really smart and hard-working scientists, who really sweat the details.
Is this the last word on handwashing? I doubt it. We’ve got at least one more paper from Dane’s dissertation in the pipeline, and I’ve still got more ideas. If anyone reading this believes that industry funded research is somehow tainted, and you’ve got $250,000, please get in touch.
That’s the background and shows just how much good scientists sweat the details, whereas any hack can make a claim, spread it on the Internet, supported by no data, just interpretation.
I’ve got a modest 70 peer-reviewed papers, book chapters and a book, but when I had a big lab with the money flowing, I got bored. That’s just me.
Surprisingly I still get cited in peer-reviewed journals a few times a week, so I know I’ve got a body of work that people go to.
Thee scandals of pay-for-publication journals are a smear on the scientific community, but until someone comes up with a better system, peer-review largely works.
I’ve kept my mouth shut for years while papers got written, reviewed and published.
No PR before publication.
Those who do are attention-seeking assholes and another smear on the profession.
Washing our hands can keep us from spreading germs and getting sick. But a new Rutgers-New Brunswick study found that cool water removes the same amount of harmful bacteria as hot.
“People need to feel comfortable when they are washing their hands but as far as effectiveness, this study shows us that the temperature of the water used didn’t matter,” said Donald Schaffner, distinguished professor and extension specialist in food science.
In the Rutgers study, published in the June issue of the Journal of Food Protection, high levels of a harmless bacteria were put on the hands of 21 participants multiple times over a six-month period before they were asked to wash their hands in 60-degree, 79-degree or 100-degree water temperatures using 0.5 ml, 1 ml or 2 ml volumes of soap.
“This study may have significant implications towards water energy, since using cold water saves more energy than warm or hot water,” said Schaffner. “Also we learned even washing for 10 seconds significantly removed bacteria from the hands.”
While the study indicates that there is no difference between the amount of soap used, more work needs to be done to understand exactly how much and what type of soap is needed to remove harmful microbes from hands, said co-author Jim Arbogast, vice president of Hygiene Sciences and Public Health Advancements for GOJO. “This is important because the biggest public health need is to increase handwashing or hand sanitizing by foodservice workers and the public before eating, preparing food and after using the restroom,” Arbogast said.
These findings are significant, particularly to the restaurant and food industry, because the U.S. Food and Drug Administration issues guidelines, every four years, to states. Those guidelines currently recommend that plumbing systems at food establishments and restaurants deliver water at 100 degrees Fahrenheit for handwashing.
Schaffner said the issue of water temperature has been debated for a number of years without enough science to back-up any recommendation to change the policy guidelines or provide proof that water temperature makes a difference in hand hygiene. Many states, in fact, interpret the FDA guidelines as a requirement that water temperature for handwashing must be 100 degrees, he said.
The FDA is scheduled to hold a conference in 2018 to discuss the existing code and any modifications that should be made and Schaffner would like to see the water temperature policy revised at that time.
“I think this study indicates that there should be a policy change,” said Schaffner. “Instead of having a temperature requirement, the policy should only say that comfortable or warm water needs to be delivered. We are wasting energy to heat water to a level that is not necessary.”
My first reaction to any food safety claim, policy or recommendation is, are fewer people going to barf?
Which greeting is the cleanest?
I usually don’t get an answer.
Because it’s really hard to associate policy with rates of barfing.
A couple of weeks ago, Karen Weintraub of The New York Times wrote: With the recent increase in use of sanitizers (hand lotions, wipes for supermarket carts, etc.) has there been any real impact on transmission of colds, flu or other diseases?
The short answer is no one knows, because no one has studied whether hand sanitizers have cut down on the number of infectious diseases among the public at large.
On a personal level, good hand hygiene clearly can make a difference in health. A 2008 study in The American Journal of Public Health concluded that improvements in hand hygiene, regardless of how the participants cleaned their hands, cut gastrointestinal diseases by 31 percent, and respiratory infections by 21 percent.
The key to stopping disease is breaking the chain that allows pathogens to be transmitted from person to person. Either hand washing or sanitizing can do that.
Sally Bloomfield, an expert in hand hygiene and an honorary professor at the London School of Hygiene and Tropical Medicine, said she always carries hand sanitizer with her when she travels. “London airport bathrooms are usually fine because they are well designed to make sure we wash our hands properly — and dry them properly,” she said, but some train “loos” leave something to be desired.
Grocery carts can be particularly risky points of transmission. Someone grabbing chicken or meat can leak the juices onto a cart and their hands, and then continue to push the cart around, transmitting pathogens like Salmonella and E. coli onto the handle. The next person who handles the cart, or the next child who sits in the top of the wagon, can then pick up the bugs.
“If you can wipe down the handle bars on the shopping cart with an alcohol-containing preparation, that’s probably a good idea,” said Dr. Cody Meissner, chief of the division of pediatric infectious disease at Floating Hospital for Children at Tufts Medical Center in Boston.
That said, Dr. Meissner and others cautioned against germaphobia. Every surface around us is coated in bacteria and other microbes, the vast majority of which are neutral or beneficial, said Liz Scott, chairwoman of the department of public health at Simmons College in Boston.
“We really need to target our hygiene practices,” she said, focusing on likely chains of transmission. That means washing your hands when you get back from the grocery store, public transit or any other public place, said Dr. Scott, who also admits to avoiding handshakes whenever possible, especially during flu season.
(The pic, above left, is from a TV commercial Dettol shot at Sorenne’s school – she’s one of the blurred out kids, second row, far right).
Long before Instagram and YouTube, the barfblog crew — I can’t believe I just wrote that, I never called my lab members the crew but I did call them the kids, even if I was the immature one — we were making food safety videos and taking pictures.
Just didn’t know what to do with them.
We had an entire website devoted to handwashing signs in bathrooms — as you do.
And then when I moved to Kansas in early 2006, it sorta got lost.
Someone in the lab was taking care of it and I was posting pictures of bathrooms from our trip to France, as we sat on the coast of Marseilles, but then the University of Guelph decided the sandbox wasn’t big enough for both of us so kicked me out.
Twelve years after Chapman and I set out for Prince George, B.C., where Chapman announced his fears of both bears and jello-swim nights at the local college, and then went to Kansas State University, where I met a girl (who’s still my best friend and wife), where I got sexually advanced upon in an unpleasant manner by a professor dude, where I had lunch with the president, got a job offer, and enjoyed a great career, my former boss sent me this:
KState has changed its handwashing recommendations.
They disconnected the blow dryers in those groovy all-in-one handwashing units.
One reason I was offered the job is because I took the prez to the bathroom and showed him how shitty their handwashing recommendations were.
But that story is old.
No one should be recreating their past glory days (and if I ever quote a Bruce Springsteen song again, put me out of my misery).
Change does sometimes happen: usually not as fast as any of us would like.
This is what is infuriating about food safety government types: they have the budgets, they have the knowledge, but they don’t have the wherewithal to confront an issue on a public scale.
They can say, oooohhh, we use social media to track when people are barfing but they do no evaluation of their alleged interventions.
Telling people to wash their hands doesn’t mean people will wash their hands.
Elizabeth Cassin of BBC writes if you’re suffering with projectile vomiting and watery diarrhea, reach for your phone and post an update.
While it won’t ease your suffering, a tweet or two could help researchers track the spread of the winter vomiting bug (which the rest of the world calls Norovirus).
The UK Food Standards Agency has been using social media to track levels of norovirus, a highly contagious illness which spreads via food and through person-to-person contact. The symptoms usually last for one to two days, with the person remaining infectious for a further two days.
If you’ve ever had, it you know what it means: vomiting, diarrhea, pain, and the general feeling of having been run over by a car.
In 2013, the Foods Standards Agency started looking at new ways to track the virus. They analysed Google searches but found that social media was a better source of data. “It’s more about the immediacy… what’s happening in their lives right now,” says Dr Sian Thomas.
On the other hand, “if you’re in hospital or a nursing home and you’re sick, then they might take a sample and send it to a laboratory for analysis,” she says.
The FSA compared this official sample data with the volume of relevant tweets and concluded that “there’s a really good correlation between the number of mentions on Twitter of ‘sick’ and a range of search terms, with the incidents of illness as defined by laboratory reports.”
“Our current estimate is that between 70-80% of the time, we are able to accurately predict an increase the next week.”
If the team predict a national outbreak, they plan to run a digital campaign explaining how to look after yourself.
“The intervention is really quite basic,” she notes. “It’s about washing your hands, it’s about looking after yourself, and not coming in to contact with other people while you’re sick.”
Norovirus can be dangerous for children or the elderly. Fortunately for healthy adults though, the illness is usually a minor, if messy, inconvenience.
“The guidelines outline sequential handwashing steps that need to be followed, including use of warm water, soap, paper towels, and continuing for 20 seconds. This study confirms the results of previous studies in this area that there is a need for funding of education and training about proper hand hygiene.”
Water temp doesn’t matter. 20 seconds doesn’t matter. And give us more money to ingratiate ourselves with future funders.
Anyone who has worked in a daycare or restaurant, for lousy pay, knows that time constraints and screaming babies sometimes interfere with best practice. Did anyone follow the guidelines? Acknowledge the realities of the world we’re in, and offer practical advice. But you’ll probably get funded in the next round.
Child care personnel properly clean their hands less than a quarter of the times they are supposed to, according to a study published in the December issue of the American Journal of Infection Control, the official journal of the Association for Professionals in Infection Control and Epidemiology (APIC, http://www.apic.org).
A new study from the University of Arkansas used video cameras to record handwashing habits and compliance among child care workers at an early childhood center in northwest Arkansas. The researchers found that personnel and parents at the facility on average followed proper handwashing procedures only 22 percent of the time before and/or after tasks such as wiping noses, emptying garbage cans, preparing food, changing diapers, or using their cell phones. Caregivers washed 30 percent of the time it was called for, with paraprofessional aides at 11 percent, and parents at 4 percent.
“Handwashing is an important component of reducing illness transmission among children in early childhood centers, especially for the adults in charge of their care,” said lead study author Jennifer Henk, PhD. “As we seek to improve overall quality in early childhood settings, our study shows the need to adopt creative strategies to increase handwashing compliance and efficacy.”
Surveillance cameras were used to randomly record 25 hours of handwashing compliance in ten different classrooms. The center was aware of the cameras, but not alerted to the primary purpose of the study. There were a total of 349 handwashing opportunities in the 25 hours; 78 corresponding handwashing events took place for an overall compliance rate of 22 percent. Handwashing opportunities and events were based on guidelines for early child care established by the American Academy of Pediatrics. The guidelines outline sequential handwashing steps that need to be followed, including use of warm water, soap, paper towels, and continuing for 20 seconds. This study confirms the results of previous studies in this area that there is a need for funding of education and training about proper hand hygiene.
“Hand hygiene in early childhood centers is especially important because children under five years of age have only partially developed immune systems, increasing their susceptibility to communicable diseases,” said Susan Dolan, RN, MS, CIC, FAPIC, president of APIC. “Studies have shown that children who spend time in an early childhood care center are two to three times more likely to acquire infections than children cared for in the home, with respiratory and gastrointestinal infections posing the highest risks.”
Handwashing can prevent about 30 percent of diarrhea-related sicknesses and about 20 percent of respiratory infection in children, according to the Centers for Disease Control and Prevention.
So what are the creative strategies to increase handwashing compliance? Waste of time.
Food Safety Talk, a bi-weekly podcast for food safety nerds, by food safety nerds. The podcast is hosted by Ben Chapman and barfblog contributor Don Schaffner, Extension Specialist in Food Science and Professor at Rutgers University. Every two weeks or so, Ben and Don get together virtually and talk for about an hour.
They talk about what’s on their minds or in the news regarding food safety, and popular culture. They strive to be relevant, funny and informative — sometimes they succeed. You can download the audio recordings right from the website, or subscribe using iTunes.
Janet Hughes of Gloucestershire Live writes that scientists are checking to see if summer holiday visits to animal attractions are behind a massive spike in the number of toddlers with cryptosporidium.
Public health chiefs are asking affected families to fill in questionnaires about where they have been and what they have eaten in an effort to trace the source of the outbreak which is particularly bad in Gloucestershire and Wiltshire.
Children aged between one and five years are most at risk from the parasite cryptosporidium which is three or four times more prevalent than normal this summer.
Doctors believe a small number of cases could be linked Oasis leisure centre in Swindon, which has been closed as a precautionary measure, and say swimming in contaminated lakes, rivers or swimming pools can cause the disease to strike.
But many of those struck down are young toddlers so other possible theories include the prospect that children might not have washed their hands after petting animals at attractions during the summer holidays.