What is not clear in this new article is that the research that serves as the basis looks at 30 years of data using metanalysis. Has control of Listeria improved dramatically in the last 30 years? Absolutely. Even the research publication mentions this. Yes, deli meats are a risk, but there have been far less cases over the past decade with the last notable case in 2020 . But there are items like salads and cheese that stand out.
Doing a metanalysis over the past 30 years does not take into account the factor of time and improvement that has occurred in that period. Secondly, the technology for identification (WGS) and tracking has improved dramatically.
Looking that the CDC website for the listed outbreaks over the past decade:
Looking that the CDC website for the listed outbreaks over the past decade:
2022
Brie and Camembert Cheese – ListeriosisIce Cream – Listeriosis
2021
Dole Packaged Salads – ListeriosisFresh Express Packaged Salads – ListeriosisFully Cooked Chicken – Listeriosis
Queso Fresco – Listeriosis
2020
Deli Meats – ListeriosisEnoki Mushrooms – Listeriosis
2019
Hard-boiled Eggs – ListeriosisNot Identified - Listeria monocytogenes InfectionsDeli-Sliced Meats and Cheeses – Listeriosis
2018
Pork Products – ListeriosisDeli Ham – Listeriosis
2017
Vulto Creamery Soft Raw Milk Cheese – Listeriosis
2016
Frozen Vegetables – ListeriosisRaw Milk – ListeriosisPackaged Salads – Listeriosis
2015
Soft Cheeses – ListeriosisIce Cream – Listeriosis
2014
Commercially Produced, Prepackaged Caramel Apples – ListeriosisBean Sprouts – ListeriosisCheese – ListeriosisDairy Products – Listeriosis
2013
Cheese – Listeriosis
2012
Ricotta Salata Cheese – Listeriosis
2011
Cantaloupes – Listeriosis
International Journal of Food Microbiology
Volume 383, 16 December 2022, 109932
Quantitative risk assessment model to investigate the public health impact of varying Listeria monocytogenes allowable levels in different food commodities: A retrospective analysis
Abstract
Invasive listeriosis is a potentially fatal foodborne disease that according to this study may affect up to 32.9 % of the US population considered as increased risk and including people with underlying conditions and co-morbidities. Listeria monocytogenes has been scrutinized in research and surveillance programs worldwide in Ready-to-Eat (RTE) food commodities (RTE salads, deli meats, soft/semi-soft cheese, seafood) and frozen vegetables in the last 30 years with an estimated overall prevalence of 1.4–9.9 % worldwide (WD) and 0.5–3.8 % in the United States (US). Current L. monocytogenes control efforts have led to a prevalence reduction in the last 5 years of 4.9–62.9 % (WD) and 12.4–92.7 % (US). A quantitative risk assessment model was developed, estimating the probability of infection in the US susceptible population to be 10–10,000× higher than general population and the total number of estimated cases in the US was 1044 and 2089 cases by using the FAO/WHO and Pouillot dose-response models. Most cases were attributed to deli meats (>90 % of cases) followed by RTE salads (3.9–4.5 %), soft and semi-soft cheese and RTE seafood (0.5–1.0 %) and frozen vegetables (0.2–0.3 %). Cases attributed to the increased risk population corresponded to 96.6–98.0 % of the total cases with the highly susceptible population responsible for 46.9–80.1 % of the cases. Removing product lots with a concentration higher than 1 CFU/g reduced the prevalence of contamination by 15.7–88.3 % and number of cases by 55.9–100 %. Introducing lot-by-lot testing and defining allowable quantitative regulatory limits for low-risk RTE commodities may reduce the public health impact of L. monocytogenes and improve the availability of enumeration data.
