Category Archives: Food Poisoning

USA – FDA Sampling of Romaine Lettuce in Yuma Finds No Widespread STEC or Salmonella Contamination

Food Safety Tech

Following last year’s widespread E.coli O157 outbreak involving romaine lettuce linked to the Yuma, Arizona growing region (Spring 2018), FDA launched a sampling assignment to test romaine lettuce for pathogenic Shiga toxin-producing Escherichia coli (STEC) and Salmonella spp. The microbiological surveillance samplingbegan on December 18, 2018 in the Yuma region and focused on 26 commercial coolers and cold storage facilities to allow FDA to sample multiple farms from several locations at once. The agency collected and tested a total of 188 samples for both pathogens. It did not detect Salmonella in any sample; STEC was detected in one sample, but additional analysis found that the bacteria was not pathogenic.

“The findings of this assignment suggest that there was no widespread Salmonella or STEC contamination of romaine lettuce from the Yuma growing region during the period when sampling occurred. As a next step, the FDA is working with leafy green stakeholders in the Yuma region to consider a longer-term environmental study to identify and control risks that will prevent future outbreaks, with the ultimate goal of protecting consumers. – FDA

The point of the sampling assignment was to determine whether target pathogens were present, and if so, to respond quickly before contaminated products reached consumers.

USA – AWERS Grained Salmon Caviar Recalled For Possible Botulism

Food Poisoning Bulletin

AWERS Inc. of Bellevue, Washington is recalling Grained Salmon Caviar in 95 gram tins because it may be contaminated with botulinum toxin, which can cause life-threatening illness or death. Do not eat this product even if it does not look or smell spoiled. Botulinum toxin does not change the appearance, taste, or texture of food. No illnesses have been reported to date in connection with this issue.

Canada – Food Recall Warning – Rosemount brand cooked diced chicken meat recalled due to Listeria monocytogenes


Recall details

Ottawa, August 18, 2019 – Rosemount Sales and Marketing is recalling Rosemount brand cooked diced chicken meat from the marketplace due to possible Listeria monocytogenes contamination. Consumers should not consume and distributors, retailers and food service establishments such as hotels, restaurants, cafeterias, hospitals and nursing homes should not sell or use the recalled products described below.

Recalled products

Common Name Size UPC Code(s) on Product
Cooked diced chicken meat 13 mm – ½” (#16305) 4.54 kg 2 06 20263 12454 7 PACKDATE: 01/21/19

Research – Whole Genome Sequencing Characterization of Shiga Toxin–Producing Escherichia coli Isolated from Flour from Swiss Retail Markets

Journal of Food Protection


Shiga toxin–producing Escherichia coli (STEC) strains are often found in food and cause human infections. Although STEC O157:H7 is most often responsible for human disease, various non-O157 subtypes have caused individual human infections or outbreaks. The importance of STEC serogroup typing is decreasing while detection of virulence gene patterns has become more relevant. Whole genome sequencing (WGS) reveals the entire spectrum of pathogen information, such as toxin variant, serotype, sequence type, and virulence factors. Flour has not been considered as a vector for STEC; however, this product has been associated with several STEC outbreaks in the last decade. Flour is a natural product, and milling does not include a germ-reducing step. Flour is rarely eaten raw, but the risks associated with the consumption of unbaked dough are probably underestimated. The aim of this study was to determine the prevalence of STEC in flour samples (n = 93) collected from Swiss markets and to fully characterize the isolates by PCR assay and WGS. The prevalence of STEC in these flour samples was 10.8% as indicated by PCR, and a total of 10 STEC strains were isolated (two flour samples were positive for two STEC subtypes). We found one stx2-positve STEC isolate belonging to the classic serogroups frequently associated with outbreaks that could potentially cause severe disease. However, we also found several other common or less common STEC subtypes with diverse virulence patterns. Our results reveal the benefits of WGS as a characterization tool and that flour is a potentially and probably underestimated source for STEC infections in humans.

  • Several STEC serotypes, including O26, were isolated from 8 (8.6%) of 93 flour samples.

  • STEC isolates from flour had a variety of virulence patterns.

  • Flour is a probably underestimated source of STEC infections in humans.

  • WGS for STEC characterization is more comprehensive than common serotyping.

Research – Conditions at the time of inoculation influence survival of attenuated Escherichia coli O157:H7 on field-inoculated lettuce

Science Direct


Higher percentages of E. coli–positive plants recovered when inoculation was closer to harvest.

Higher relative humidity and leaf surface wetness were measured during night inoculation.

Short-term smaller initial population declines were observed after night inoculation.

E. coli population sizes were similar 2 or more days after night or day inoculation.

Probability of detecting E. coli was higher for longer times when inoculated at higher levels.


The impact of plant development, environmental conditions at the time of inoculation, and inoculum concentration on survival of attenuated BSL1 Escherichia coli O157:H7 strain ATCC 700728 on field-grown romaine lettuce was evaluated over 3 years. E. coli 700728 was inoculated onto 4- and 6-week-old romaine lettuce plants in the Salinas Valley, CA, at night or the next morning with either low (5 log) or high (7 log) cell numbers per plant to simulate a single aqueous contamination event. At night, when leaf wetness and humidity levels were high, E. coli cell numbers declined by 0.5 log CFU/plant over the first 8–10 h. When applied in the morning, E. coli populations declined up to 2 log CFU/plant within 2 h. However, similar numbers of E. coli were retrieved from lettuce plants at 2 and 7 days. E. coli cell numbers per plant were significantly lower (P < 0.05) 7 days after application onto 4-week-old compared to 6-week-old plants. E. coli 700728 could be recovered by plating or enrichment from a greater proportion of plants for longer times when inoculated at high compared with low initial concentrations and after inoculation of 6-week-old plants compared with 4-week-old plants, even at the low initial inoculum. A contamination event near harvest or when leaf wetness and humidity levels are high may enhance survivability, even when low numbers of E. coli are introduced.

RASFF Alerts – Ochratoxin A – Raisins – Pistachios – Raisin Fruit Filling – Dried Grapes –


RASFF – ochratoxin A (20.6 µg/kg – ppb) in raisins from Turkey in the UK

RASFF – ochratoxin A (71 µg/kg – ppb) in pistachios from the United States in the Netherlands

RASFF – ochratoxin A (18 µg/kg – ppb) in raisins from Turkey in France

RASFF – ochratoxin A (19.7 µg/kg – ppb) in raisin fruit filling from the Czech Republic in the Czech Republic

RASFF – ochratoxin A (17 µg/kg – ppb) in dried grapes from Turkey in France

RASFF – ochratoxin A (53 µg/kg – ppb) in pistachios from the United States in the Netherlands

RASFF Alerts – Aflatoxin – Blanched Groundnuts – Shelled Peanuts – Nutmeg – Peanuts


RASFF – aflatoxins (B1 = 11.0; Tot. = 12.7 µg/kg – ppb) in blanched groundnut kernels from China in the UK

RASFF – aflatoxins (B1 = 204; Tot. = 244 µg/kg – ppb) in shelled peanuts from Angola in Portugal

RASFF – aflatoxins (B1 = 12; Tot. = 12 µg/kg – ppb) in nutmeg from Indonesia in the Netherlands

RASFF – aflatoxins (B1 = 7.1; Tot. = 8.6 µg/kg – ppb) in peanuts from Brazil in Spain