Call for Revision of Listeriosis Guidelines for Safer Pregnancy

A new discovery about Listeria by a team of midwife-researchers boasted a surprising lead—two academically accelerated high school students. The students, Valentina Simon and Rachel Rosenzweig, are both 14 years old. They were accompanied in their research by professional midwives Katya Simon, Mickey Gillmor, and Rebeca Barroso, under the guidance of University of Maryland food scientist Bob Buchanan, PhD. Together, they published an evaluation of listeriosis prevention guidelines in the Journal of Midwifery and Women’s Health that revealed current guidelines were growing less effective over time.

“Rachel and I looked at six categories of foods included within the 800 cases highlighted in the government databases,” says Simon. “Six categories were the recommended foods to avoid, and we added a seventh ‘other’ category. We quickly noticed that the current avoidance guidelines only prevented listeriosis cases prior to the year 2000, which is very alarming. We then looked at the years 2015-2016 and found that only 5 percent of confirmed Listeria related infections stemmed from the six official food groups outlined in the guidelines.”

Previously, Simon and Rosenzweig and their team noted, Listeria was detected in raw milk, unpasteurized soft cheeses, unwashed raw produce, smoked seafood, and hot dogs. However, after considering the variety of products listed in the FDA and USDA food-recall databases, they noticed that listeriosis was on the rise in ready-to-eat meals and salads, frozen foods, and pasteurized dairy products.

“This is a major finding for Valentina and Rachel,” comments Dr. Buchanan. “I was thrilled when they reached out to me for help interpreting the data. From the start, I encouraged them to research and publish the total number of listeriosis cases as opposed to only identified cases. The CDC will only report identified cases, so going a layer deeper and discovering how many total people have been infected with Listeria and the causation of each has really strengthened their paper,” says Dr. Buchanan. “Within their paper, Valentina and Rachel have published a very eye-opening table that demonstrates the rise in total cases from 2007-2014 from non-traditional foods. This is clear evidence that additional foods may need to be reflected within the CDC guidelines.”

Deirdre Schlunegger, CEO of Chicago’s Stop Foodborne Illness, praises Dr. Buchanan for his guidance.

“Bob Buchanan is passionate about food safety and I’m glad to see his mentorship here,” she tells Food Quality & Safety. “It is also significant that they discovered that only 5 percent of confirmed Listeria-related infections come from the six official food groups outlined in the current guidelines. It is critical to be current in statistics and to look at all cases.”

Schlunegger suspects that advanced technology is helping identify Listeria where officials were unable to recognize it previously, but adds food producers need to be planning for Listeria avoidance from the beginning.

“Industry needs to be as proactive as they can be in educating consumers about their products and their risks,” she says. “It is that simple and in the end it saves them money and a crisis. Of course, consumers have responsibilities too, but often they don’t know what they don’t know.”

Josh Bloom, PhD, senior director of chemical and pharmaceutical sciences for the American Council on Science and Health, says increases in Listeria have paralleled public embrace of unpasteurized products.

“These were the predominant (and new) foods that the girls found to be responsible for the increases,” he says. “The unpasteurized/raw industry is dangerous and should go away. It is not an industry. It is a cult. There is no warning label other than ‘throw this s–t out’ that will accomplish anything. Ready-to-eat salads have been killing and making people sick for some time (the still-ongoing romaine lettuce E. coli outbreak).”