Food Safety Talk episode 52: A Keene epidemiologist

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.bill.keene_.portland

The guys started the show dreaming about a Red Mac Pro. They then turned to the passing of Bill Keene. Bill has been mentioned in various FST episodes and was a well respected epidemiologist as seen in the articles by the Oregonian and Doug Powell. The guys then turned to their beverages, Coffee Club, Napoleon Dynamite, Homeland, and Car Talk. Ben shared his preference for Aussie Rule football and Arcade Fire’s album Reflektor. The conversation then turned to Don’s limited iPhone music library, Privateering and Dire Straights, which reminded Ben of Money for Nothing and WWE Wrestling (not WWF Wrestling). To finish they talked about Christmas music, Bad Religion’s Christmas Songs, Coulton and Roderick’s One Christmas at a Time and Horrible Christmas songs.

Ben confused IAFP’s History with Bug Trivia and shared Julian Cox’s information about the 1960′s, and this evolved into a broader discussion about the IAFP and its membership.

The discussion then turned back to Bill Keene and some of the outbreaks he had been involved in. This included a Salmonella Panama outbreak (not to be confused with Van Halen’s Panama), which was the first outbreak that was solved through the innovative use of supermarket loyalty cards and that Bill and others were sued for (the lawsuit was eventually dropped.. The guys then discussed outbreak investigation in some detail and that public health officials are damned if they do and damned if they don’t name commodities and suppliers. There is of course always a risk of getting the epidemiology wrong, as was the case with Salmonella Saintpaul in peppers. Finally, Bill’s investigation of a Norovirus outbreak reminded Ben of a recent Norovirus outbreak in Las Vegas.

Then Ben commented on an exchange with Chris Gunter, who was presenting on traceability for small producers at the 2013 Strawberry Expo. Chris’ presentation is based on the investigation of an E. coli O157 outbreak related to strawberries, in which Bill Keene played a part.

In the after dark, the guys reflected on mortality and that we should all Enjoy Every Sandwich. And because they love him,  Rob Ford got a mention again and again.

Deadly outbreaks: How medical detectives save lives threatened by killer pandemics, exotic viruses, and drug-resistant parasites

Atif Kukaswadia writes in this review on Public Health Perspectives blog: Anyone who follows my writing knows that I’m a big proponent of using stories to talk about science. We’ve discussed how you can use science fiction teach science, zombies to talk about disease outbreaks, and my TEDx talk discussed using principles of storytelling in how we discuss science. So when I was asked to review (see disclaimer below) Dr sandwichAlexandra Levitt’s new book “Deadly Outbreaks: How Medical Detectives Save Lives Threatened by Killer Pandemics, Exotic Viruses and Drug-Resistant Parasites,” I jumped on the opportunity.

The CDC has a program known as the Epidemiologic Intelligence Services, where individuals trained in fields such as epidemiology, medicine, statistics and veterinary sciences come together to identify causes of diseases. For an overview of the EIS, check out this review of “Inside the Outbreaks” by Travis Saunders over at Obesity Panacea. The EIS was set up Alexander Langmuir, who has been profiled on the blog, and their work has been instrumental in learning about, and thus containing, disease outbreaks all over the world. Dr Levitt is well positioned to speak on these issues, having worked at the CDC since 1995, although it should be noted that this was written in her free time, not as part of her position at the CDC.

The book is comprised of 7 distinct chapters, each one covering a unique disease outbreak. In an almost “House-ian” style, the EIS agent will hear about an outbreak, go into an area, and then have to uncover what it is that is causing people to get sick, often with very little information to go on. I’m going to keep the details deliberately vague, as part of the joy of reading the book is guessing what is causing the outbreak, and following the train of thought of the investigators.

Another thing I really enjoyed about the book was how Dr Levitt deals with all important stakeholders, and talks about their history. One chapter deals with a Native American population that has undergone a disease outbreak, and does a great job explaining the history of these people. This is very pertinent information, as the problems of going into this community are a direct result of how these communities have been treated historically, and everything from the equipment you bring in, to the name of the disease, has to be cleared by elders and community leaders. The history of a group is something public health practitioners need to be aware of and sensitive to in order to work with these people to identify causes of disease, and this was illustrated well in this book.

Finally, at a more stylistic level, a conscious decision the author makes is to provide context for the characters. For example, in Chapter 1 the “protagonist” is eagerly anticipating her wedding, and at one point goes for dinner and discusses this with a colleague while talking about the case at hand. In a later chapter, the author describes Dr Stacy Holzbauer, a veterinarian, as someone whose “plan was to become a Sopranos_season3_episode01large-animal veterianian, marry a cowboy, live on a ranch on the Great Plains, and raise cowboys,” a vivid and charming description. While she did become a veterinarian, she then pursued a MPH and now does brilliant public health work. This makes the characters that much more fleshed out and human, rather than being 2-dimensional and alien, a welcome respite from the socially awkward, comically inept, and often evil, scientist of television and film. At points I found this transition jarring, but it adds to the overall feel of the book, and I think helps the book connect with the general public.

And the general public, especially those with an interest in public health, is the target audience. I would recommend this book to those interested in learning more about public health, both from an infectious disease epidemiology.WATER PUMP3_Page_4standpoint, as well as from a practical, i.e. how do we actually investigate disease outbreaks, standpoint. It’s written for a lay audience, and avoids jargon and delving too far into statistics or biology, which makes it easy and straightforward to follow. If you’re considering pursuing an MPH and want to do “shoe leather epidemiology,” it’s a must read.

6 sickened; Salmonella-contaminated blueberries from Georgia in 2010 tracked down by Minn. health types using GTINs and shopper cards


In August 2010, the Minnesota Department of Agriculture and Minnesota Department of Health investigated an outbreak of six cases of Salmonella Newport infection occurring in northwestern Minnesota, which identified fresh blueberries as the cause. Initially, traditional traceback methods involving the blueberryreview of invoices and bills of lading were used to attempt to identify the source of the outbreak. When these methods failed, novel traceback methods were used. Specifically, supplier-specific 12-digit Global Trade Item Numbers (GTINs) and shopper-card information were used to identify a single blueberry grower linked to cases, corroborating the results of a case-control study in which consuming fresh blueberries was statistically associated with illness (5 of 5 cases versus 8 of 19 controls, matched odds ratio [MOR] undefined, P = 0.02). Consuming fresh blueberries from retailer A was also statistically associated with illness (3 of 3 cases versus 3 of 18 controls, MOR undefined, P = 0.03). Based on initially incomplete evidence in this investigation, the invoices pointed to wholesaler A and grower A, based on first-in-first-out product rotation. However, when point-of-sale data were analyzed and linked to shopper-card information, a common GTIN was identified. This information led to an on-site record evaluation at retailer A, and the discovery of additional records at this location documented the supply chain from grower B to wholesaler C to retailer A, shifting the focus of the investigation from grower A to grower B. This investigation demonstrates the emerging concepts of Critical Tracking Events (CTEs) and Key Data Elements (KDE) related to food product tracing. The use of these shopper-cased data and the event data that were queried by investigators demonstrates the potential utility of consciously designed CTEs and KDEs at critical points in the supply chain to better facilitate product tracing.

Use of Global Trade Item Numbers in the investigation of a Salmonella newport outbreak associated with blueberries in Minnesota, 2010

Journal of Food Protection®, Number 5, May 2013, pp. 744-918 , pp. 762-769(8)

Miller, Benjamin D.; Rigdon, Carrie E.; Robinson, Trisha J.; Hedberg, Craig; Smith, Kirk E.

Tracking sickness through social networks – practical use during an E. coli O157 outbreak in a primary school in London

This paper describes the practical use of social network diagrams in the management of an outbreak of Escherichia coli O157 (VTEC) in a primary school in London. The diagrams were created during the outbreak to establish the extent nurseryand nature of person-to-person transmission in the cases and their contacts. The diagrams supported a tailored public health action, and hence aided in the control of the outbreak. We conclude that for selected infectious diseases, social network diagrams can provide a valuable tool in the management of an outbreak.

Epidemiology and Infection / FirstView Article, pp 1-9

D. Devakumar, A. Kitching, D. Zenner, A. Tostmann and M. Meltzer

Epidemiology witches don’t get enough credit

Foodborne illness outbreaks are messy. Not just for the unlucky individuals feeling the consequences in the bathroom, but for investigators and business owners. An outbreak is rarely solved with a smoking gun (like a pile of deer poop). Often the source is determined by the Nate-Silveresque witches in the epidemiology department. I’m in awe of the folks who take the available data well after an incident happens and utilize statistics to uncover clues to a vomit or diarrhea mystery.  wizard_of_oz_0456_wicked_witch

Looking at the predictable responses that often pop up from business operators during an outbreak investigation, I’m not sure a lot of other folks outside the food safety world share this awe. All they seem to want to see are test results.

Count Ming Chang of Ming’s Sushi and Dimsum in the ever-so-exciting home of the Petes, Peterborough, Ontario (that’s in Canada) as someone who needs to see a Salmonella-positive sample to be convinced.

Lance Anderson of My Kawartha quotes Chang as saying, “They found nothing” (meaning no positive samples).

Ming Chang, owner of the Lansdowne Street West restaurant, says the local health unit gave the green light to reopen morning after all salmonella testing turned up negative results.

According to the health unit, in December 18 salmonella cases were identified from patrons who had eaten at the restaurant.

Mr. Chang isn’t convinced to outbreak started at his restaurant considering all tests the health unit conducted came back negative.”It could have come from anywhere,” he adds (yeah, but the epidemiological data the health unit has seems to point to Ming’s).

Mr. Chang says the health unit shut him down after some people got sick even though salmonella wasn’t found in the business. “They went on people’s testimonies. Basically I was found guilty before being proven guilty,” says Mr. Chang.”We’ve passed all our inspections here for the past two years.”

Maybe epidemiology’s image needs a makeover. If only it was called Kardashiology, maybe folks would pay attention.

Did bad berliners sicken over 100 in South Australia with Salmonella

Beginning in Jan. 2011, 107 people in South Australia were sickened with Salmonella linked to custard-filled berliners.

Yesterday, the State Government told the Supreme Court it spoke truth when it blamed iconic baker Vili Milisits as the source.

Mr Milisits has asserted public health director Dr Kevin Buckett defamed him in two press conferences and one radio interview by blaming the berliners for food poisoning that affected more than 100 people.

John Whitington, acting for Mr Milisits, was quoted by the Herald Sun as saying, “The Government says the Department of Health conducted investigations, in late January, as a result of increased incidence of reported Salmonella. It says a statistically-significant proportion of people were interviewed.

“It says that, based on that analysis, a person infected with the salmonella bacteria was 38 times more likely to have eaten a custard-filled berliner.”

He asked Judge Brian Withers to order the Government to release that material to Mr Milisits’ legal team, along with the names of the people interviewed.

Judge Withers has reserved his decision.


327 sick in prison with Salmonella, 2009

What’s worse than being in prison? Being in prison in the middle of a Salmonella outbreak (I can think of other things but this is a food safety site).

In September 2009, an outbreak of Salmonella enterica serovar Enteritidis affected 327 of 1419 inmates at a London prison. UK health types report in Epidemiology and Infection they applied a cohort design using aggregated data from the kitchen about portions of food distributed, aligned this with individual food histories from 124 cases (18 confirmed, 106 probable) and deduced the exposures of those remaining well. Results showed that prisoners eating egg cress rolls were 26 times more likely to be ill [risk ratio 25·7, 95% confidence interval (CI) 15·5–42·8, P<0·001]. In a case/non-case multivariable analysis the adjusted odds ratio for egg cress rolls was 41·1 (95% CI 10·3–249·7, P<0·001).

The epidemiological investigation was strengthened by environmental and microbiological investigations. This paper outlines an approach to investigations in large complex settings where aggregate data for exposures may be available, and led to the development of guidelines for the management of future gastrointestinal outbreaks in prison settings.

Clooney and Keibler felled by food poisoning in Italy

I’m a big George Clooney fan. It’s related to his coolness as Batman and Danny Ocean. It seems like he never makes a bad movie (except for The American). After a week traveling with the kids, Dani and I watched The Descendants, a Clooney movie we had been saving for a while.

George was at his best; the movie was pretty great.

According to Clooney and his ex-wrestler and prolific tweeter girlfriend Stacy Keibler were not at their best earlier this week in Italy after dealing with what has been reported as food poisoning.

The couple, who were vacationing at Clooney’s Lake Como home, fell sick after a meal in Cernobbio though the manager of the restaurant in question denies all responsibility.

A source told that both Clooney and Keibler are now feeling fine after their brief bout of food poisoning.

Nevertheless, the manager of the restaurant is refusing to accept that it was his food that left the table with upset stomachs, claiming they must have gotten food poisoning elsewhere.


Foodborne disease surveillance in France: a foundation for food safety

The French published their own series of detailed foodborne disease surveillance papers, and did it the day before the Americans.

A special issue of the Bulletin épidémiologique hebdomadaire (BEH) and the Bulletin épidémiologique Anses-DGAL, May 2012, number 50, Microbiological hazards in food products of animal origin: monitoring and evaluation contains 13 research papers.

In an editorial, the author writes foodborne illness surveillance is an important and complex issue. Important because tens of thousands of cases of foodborne outbreaks are still reported each year, complicated by the difficulty in assessing and controlling the risk throughout the supply chain — from the farm to the fork.

Thanks to Albert Amgar for passing along the information and some translation.

The abstracts are available at and are available in English. They are also available in the daily bites-l listserv and at

Social media helps investigation of sapovirus gastroenteritis at 2011 Las Vegas Marathon

The annual Rock ‘n’ Roll Las Vegas Marathon and ½ Marathon was attended by about 44,000 runners on Sunday Dec. 4, 2011. By Tuesday, complaints of illness were trickling in to the Southern Nevada Health District. By Thursday, traditional media reported on increasing complaints of barfing on the event’s Facebook page. An investigation was launched.

Within a week, health-types were able to say it wasn’t the water distributed during the race that made runners sick, quelling a rumor that had already taken on a life of its own.

Below are excerpts from the final report, issued last week, identifying the first outbreak of sapovirus in Nevada and the emerging role of social media in epidemiological investigations.

Links to an epidemiology online survey were shared on the marathon’s Facebook page (with 25,732 followers) by members of the running community on four consecutive days starting on the day of release of the survey, and a total of 42 times within one week as part of a number of discussions among ill runners. Twenty-two people shared the survey link on Twitter, potentially reaching 17,982 followers. A total of 362 responses had been submitted within 12 hours of the release of the survey. After the survey had been posted for 4 days, a total of 1,146 surveys had been submitted. Of the 1,082 completed surveys, 578 (53.4%) were from persons who reported developing diarrhea or vomiting. Of these, 528 (91.3%) met the case definition.

Seventeen ill local runners were requested to provide stool specimens; specimens were provided by nine marathon runners and two symptomatic children of a symptomatic marathon runner. Specimens were collected between December 9, 2011 and December 11, 2011 (5-7 days after symptom onset), and all specimens submitted were formed stools. Two were positive by rRT-PCR for sapovirus and negative for all other tested pathogens at CDC and the SNPHL

The findings of this investigation point to the source of the sapovirus outbreak among marathon runners as a common exposure on the morning before the race, most likely at the health and fitness expo. It was not possible to determine which common exposure was responsible for the outbreak. The timing of the exposure and the incubation period of sapovirus resulted in the majority of cases becoming ill during the race or in the hours shortly after; however, exposure during the race was not the cause of the outbreak.

Sapoviruses (genus Sapovirus, family Caliciviridae) are a group of viruses that cause acute gastroenteritis in humans. Sapovirus is not as well-characterized as norovirus, but is thought to be similar to norovirus in that it has a short incubation period (1-2 days), low infectious dose, causes a self-limiting illness that is rarely serious with a significant percentage of asymptomatic infections, and is easily spread from person to person through fecal-oral transmission. Both infections cause diarrhea, although a lesser percentage of sapovirus patients develop vomiting as compared to norovirus patients.

Outbreaks of sapovirus have been reported in the literature, but reports of foodborne outbreaks and outbreaks among adults outside long-term care are rare and the majority of cases occur in children under 5 years of age. This outbreak represents the first outbreak of sapovirus in Southern Nevada and the first time the virus has been identified in the local population. However, sapovirus testing is not available locally and has not been previously ordered during an outbreak. Rather than representing a newly-introduced disease, the identification of the virus likely indicates that sapovirus circulates at low levels in the population but goes unidentified.

This investigation was also the health district’s foray into using social media as an investigative tool, rather than just as a method of disseminating information to the public. Using the active community of runners on Facebook and Twitter allowed for the rapid dissemination of the survey directly to the exposed population without a delay in requesting participant information from the race organizers. Comments posted to social media sites provided ongoing, real-time insight into the needs and concerns of the ill population, and provided a feel for the efficacy of health district investigation efforts. Comments about SNHD were overwhelmingly positive, and indicated a level of trust and willingness to cooperate from the community.

Ill and non-ill runners quickly responded to the survey, which allowed SNHD staff to rapidly identify ill persons for laboratory testing. It also allowed for a preliminary data analysis to be quickly completed, which allowed the water provided by race organizers, an early focus of complaints by runners, to be ruled out as a source of the outbreak. The water provided in the race was the same potable water that is distributed throughout Southern Nevada, and it was important to quickly determine if the general population was at risk of disease.

The ill persons identified by SNHD staff complied very quickly with the request to submit specimens for laboratory testing. The submission of stool samples for testing is often a difficult task due to the type of sample requested and the handling requirements. The ill persons were highly motivated to provide samples that could be used to identify the causative agent of the outbreak.

In the future, several steps should be implemented to improve the investigative process and to prevent disease at similar events. First, although the survey was developed quickly, a standard template should be developed to allow the rapid deployment of standardized surveys for illness. In addition, corresponding standard analytic tools should be developed to allow for the rapid analysis of survey data.

Next, SNHD should consider using social media more frequently to administer surveys given the appropriate audience; in this case, the use of Facebook was effective because there was an active community of marathon frequently posting and reading the marathon’s page. During a large event, it might be appropriate to set up a social media site for the event response. This would provide an additional avenue for SNHD to share information from the public, and following discussions would allow for real-time feedback on the needs and concerns of the public. However, the decision to launch a social media site should be thoroughly discussed prior to launch, as it would place SNHD in the role of moderating the discussion on the topic (for example, removing libelous comments or threats against employees). It would also necessitate the development of policies on the participation in such discussion by staff members on work time or personal time.

The complete report is available at: