The researchers find that air irrigation is most likely because of the contamination by E. coli de la Romaine

Epidemics of foods of food origin of infections at E. coli O157 have been established in Roman lettuce continue to be an ongoing public health problem.

The last epidemic in November and December 2024 saw 89 people through 15 states dismissed. The epidemic hospitalized 36 people and killed one.

To better understand the problem, a group of scientists has examined several factors, including irrigation water used in the production of Roman lettuce. The researchers’ examination cited a large number of epidemics, including seven between 2015 and 2021. These epidemics led to 4,274 diseases confirmed by the laboratory, which led to 766 hospitalizations and 11 deaths.

Scientists have considered a wide variety of ES contamination sources. Coli O157 of the Roman lettuce, but returned to irrigation above the head as a problem. Other factors included the runoff of fattening parks and the lack of treatment of irrigation water.

“Risk and post-harvest risk factors may include human behavior, harvest / production equipment and production water,” according to the research ratio. “In addition, the lack of treatment stages which ensure the effective elimination or the inactivation of E. coli O157 before consumption, coupled with the recent increase in the consumption of Roman, further increases the risk.”

The researchers concentrated their survey on the Roman lettuce cultivated in California and Arizona because 90% of the country’s Roman is cultivated in these states. The research model included three different irrigation systems: aerial spraying, furrow and drip.

Nine risk management strategies for the evaluation in the study analysis scenario have been identified. These scenarios were the vaccination of cattle in the fattening parks; Four scenarios involving the treatment of surface water used for aerial spray irrigation, by chlorine, peracetic acid or ultraviolet radiation; Go from aerial spray to the furrow irrigation system; Go from aerial spray and gruff irrigation furrow; Alternatives to wash the chlorine during post-harvest treatment; temperature reduction during retail; and consumer washing habits.

The accounts of E. The highest coli O157 in Roman lots were predicted when irrigation water was applied via an aerial spray system.

“On the other hand, the irrigation of the furrow or drip systems has led to E. coli O157 accounts significantly lower in the Roman lots,” according to the researchers.

“… surface water treatments and the transition to the irrigation of furrows or drips have resulted in slightly lower but very effective reductions of E. Oli O157 counts at the pre -hartleed stage, reaching between 90.5% and 96.8% of reductions in cases of median disease.

“… irrigation has become the most important source of E. Coli o157 in the fresh Roman, in particular when you consider the impact of other sources of contamination … “

The researchers have noted on several occasions that contaminated irrigation water – in particular from aerial spray methods – was a key route for contamination of E. Coli o157 of the Roman lettuce. They say that the treatment of irrigation water from surface sources – like open channels like those often used in a large part of the growth regions of California and Arizona – is a key factor in controlling E. Coli o157 of the Roman lettuce.

Study data suggested that the transition from aerial spray irrigation to the furrow or, ideally, drip irrigation systems could provide a viable solution to reduce the number of E diseases. Coli o157 of the Roman lettuce.

“Despite the introduction of many parameters specific to each irrigation system which are reasonably different from the three irrigation systems, our model suggested that the main driver behind the greatest number of disease cases associated with aerial spray irrigation was its increased direct contact capacity between irrigation water and Roman,” according to the research ratio.

“… In our study, the entirely transition of aerial spraying and irrigation in furrows with drip irrigation would have been more effective than chloration and UV treatments of surface irrigation water …”

The research study revealed that 52% of E diseases. Coli o157 caused by Roman lettuce are due to contamination by irrigation by aerial spray. Scientists have said that switching to drip or furrow irrigation systems would considerably reduce contamination.

Research for the study was supported by a subsidy from the National Institute for Food and Agriculture of USDA.

Authors and affiliations

• ECE Bulut, Sarah I. Murphy & Renata Ivanek of the Department of Population Medicine and Diagnostic Sciences, Cornell University
• Laura K. Strawn of the Department of Sciences and Food Technology, Virginia Tech
• Michelle D. Danyluk of the Department of Food Sciences and Human Nutrition, University of Florida
• Martin Wiedmann of the Department of Food Sciences at Cornell University

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