PMA’s Chief Science & Technology Officer, Dr. Bob Whitaker interviewed epidemiology expert, Dr. Michele Jay-Russell to introduce her to PMA members and provide a snapshot of her background and her passion for epidemiology.

BW: What drew you into epidemiology?

MJR: My interest in epidemiology probably started as a kid. I was always curious about animals and nature. I did my own little epi-investigation as a kid into die off of tadpoles in our neighborhood pond. After doing interviews, I discovered it was because a neighbor was putting gasoline and doing some dumping in the pond. So that was stopped. I always had a curiosity, and going into my education I was very interested in applying to veterinary school, but I didn’t take the traditional route as an undergrad. I went through medical entomology and theater as well as focusing on writing. Eventually I went into vet school and at UC Davis they have a combined program in preventive medicine and epidemiology, so I signed up for the duel degree program and knew that I would ultimately end up having a role in public health and doing epidemiologic investigation.

BW: What do you think is most misunderstood about the role of epidemiology in public health and the combination of art and science that makes up its practice? You did a great job writing these two companion papers, but what do you see most often as industry misperception of what epidemiology does?

MJR: I think the misperception relates to the strength of the association and the understanding of how statistics can be used. Having the science of epidemiology isn’t as straight forward as having for example a laboratory test. Not that all microbiology test are unambiguous but it is a lot easier to understand that you cultured E. coli O157:H7 out of a food or you didn’t versus discussing the nuances of an epidemiology investigation where you have outliers and statistical criteria. You have people that ate the contaminated food and didn’t become ill, and people who appeared not to have eaten the food and are part of the community and had an exposure. So the level of uncertainty in epidemiology is much greater than what you typically find in a standard microbiological test. Also, along that line, there is an expectation by some in the industry that you are always going to truly prove the cause of a foodborne outbreak. Sometimes that is just not possible because of the perishability of our products and the sampling limitations for testing for pathogen presence.  You have to rely on epidemiology and not having that laboratory result should not ever be an excuse not to protect public health if your epidemiology is strong. Where things get difficult is that not all epidemiology investigations are the same.  Some are stronger than others, some have weakness and uncertainty.

BW: Is there anything that makes fruits and vegetables more difficult when doing epidemiological studies versus another food group? I know that you have been involved across the board in different food groups. Is there anything about produce that is particularly different or any key learnings that you have gained over the years in cases where fruits and vegetables have been involved? 

MJR: The difficulty can be when you have an emerging vehicle or any food product that has not been seen before with a certain bacterial pathogen. For example, when strawberries were implicated with E coli. O157 earlier this year, that was not an expected vehicle. Also early on with sprouts, it took a number of repeated epidemiological studies before sprouts were actually linked to outbreaks. Some of that work was done in California by some of my colleagues, and one of their major clues was having a disproportionate number of women that were eating that produce item. The other part relates to what I was saying about having laboratory evidence. With milk, dairy, produce, and those items by time you identify the outbreak and start interviewing people that product can be long gone. And because contamination can be intermittent or in a short period of time, not ongoing, you may never isolate the implicated strain out of the food product.

BW: Ok switching gears, you just recently completed a PhD at UC Davis correct?

MJR: Yes, I did.

BW: Can you describe to PMA members what your current research interests are and how does that relate to some of the work you have done recently in the epidemiological field?

MJR: Well currently I am working as the project director in the Western Center for Food Safety at UC-Davis. I have been in this position for a little over 3 years now. The center was created with FDA to be what they call a “center for excellence” and is funded by CFSAN. Our center focuses on the interface with animal and plant agriculture as well as the environment. We in particular focus on pre-harvest food safety with an emphasis on produce. There is some dairy but the dairy component relates more towards manure management. So we do have strong produce research effort right now. Because I am a veterinarian, with a background in epidemiology, I am doing studies that primarily look at domestic and wild animals, and whether or not they are carries of foodborne pathogens, and what potential risks and mitigation strategies are available to prevent direct transmission of pathogens onto produce plants out in the field or to protect watershed from contamination by animals.

BW:  Thanks Michelle.  Also, thank you for preparing two excellent papers on epidemiology.  These papers can be found on pma.com in the “Information” section of the Food Safety Resource Center.

Meg Miller:
Hello, this is PMA public relations manager Meg Miller, and welcome back to our audio blog, “Ask Dr. Bob” with PMA’s Chief Science & Technology Officer Dr. Bob Whitaker. We have joining us special guest, Bonnie Fernandez-Fenaroli, Executive Director of the Center for Produce Safety at the University of California, Davis. Dr. Bob chairs the center’s Technical Committee and is a member of the center’s Executive Committee. The CPS has just closed its 2011 request for food safety research proposals at the end of March.

Bob, Bonnie, what should our listeners know about this new round of research request?

Bob:
First, Meg, let me set the stage…CPS and its partners sponsor research activities designed to fill basic knowledge gaps in specific areas of food safety practices for fruit, vegetable and tree nut production, harvest and post-harvest handling. The objective is to provide the produce industry with practical, translatable information that can be used at all levels throughout the supply chain. To date, CPS has funded 43 research projects with a total investment of nearly $6.8 million.

Bonnie:
That’s right Bob. Now, the center and its public and industry research partners are making $3 million available to fund general and commodity-specific projects to address additional food safety research needs in the fresh produce industry. It’s important to note that this is a global research effort. We want to reach out as widely as possible geographically. In the past we’ve had institutions in Israel and Canada doing some of the research.

Meg:
Bonnie, can you tell us what specifically the new funding request is looking for?

Bonnie:
The 2011 RFP seeks to fund both produce-general food safety questions and commodity-specific questions. Core research priorities for produce in general look to better understand risk potential and to develop more effective food safety management tools in the following areas:

• The use and cultivation practices regarding compost, soil amendment and fertilizer,
• Buffer zones for domesticated animals,
• Co-management of food safety and the environment,
• Water,
• Harvest practices,
• Post-harvest produce cooling methods,
• Post-harvest transfer of pathogens via water used during handling and processing, and
• The significance of “positive” product test results and actual capacity to cause illness.

Bob:
And, this RFP’s commodity-specific food safety research pertains to almonds, tree fruit, leafy greens, pistachios, strawberries tomatoes, and a number of different commodities.

Meg:
How did research priorities get set?

Bonnie:
The RFP’s general research priorities were identified in industry risk assessments and prioritized by the CPS Technical Committee, an independent advisory board including experts from industry, academia, government and nongovernmental organizations. That group revisits those priorities on an ongoing basis to ensure they main current. The commodity-specific research priorities were developed with industry partners. 

Bob:
The CPS Technical Committee and our research partners have a wealth of information to base decisions on. After the first CPS Symposium last year, we hosted an event with FDA to review the state of food safety knowledge in different areas.  That event gave us some ideas on where more research needed to be done. On top of that, both Bonnie and I talk with people throughout the course of the year and take this input to the CPS.  We also look back on what we’ve already funded, as well as research by others, to see if topics have been sufficiently covered or if more needs to be done. The program works very hard to stay current, be flexible, and ensure it addresses the most urgent food safety research needs and issues.

Meg:
When will these projects be implemented?

Bonnie:
Proposals were due the 31st of March, and we’ll be announcing the awarding of the projects in the fall of 2011. Projects are typically one to two years but some can be shorter.  We want to be flexible to ensure we accomplish whatever research needs to be done.

Bob:
These projects all have a pretty quick research time frame, and that indicates the practical focus of this research. We want to be very timely and very hands-on because we’re dealing with the issues growers and processors face every day.

Meg:
So how does all this research fit in with the real-world produce industry?

Bonnie:
Well, Meg, as CPS’ research programs mature, our projects represent a greater and greater part of the produce chain. We initially started with production, then added processing, and we’ll continue to identify needs further along the chain. 

Bob: 
This is such an important concept. One thing the history of outbreaks in recent years has taught us, is that we’re all in this together. So, while research looking at the survival of pathogens in a field may not seem important to someone who runs a store or restaurant, it’s actually as crucial to them as it is to the grower.  People at all points of the supply chain are affected by food safety issues. The entire industry is indeed tied together, so research at all those various points is important.

CPS also recognizes the need to evaluate research and determine when decisions can be made from the results. That’s where the CPS Symposium comes in and we’ll talk more about that next time.

Meg:
We will definitely look forward to it. Thank you Bonnie and Bob for sharing with us today how this next round of research is important to our industry. Listeners, for more information on the CPS research or the upcoming symposium, go to www.cps.ucdavis.edu.
Thanks for joining us!