Category Archives: microbial contamination

USA – USDA Announces Action to Declare Salmonella an Adulterant in Breaded Stuffed Raw Chicken Products

Posted on August 3, 2022 by | Leave a comment

FSIS USDA

The U.S. Department of Agriculture’s (USDA) Food Safety and Inspection Service (FSIS) is announcing that it will be declaring Salmonella an adulterant in breaded and stuffed raw chicken products.

“Food safety is at the heart of everything FSIS does,” said Agriculture Secretary Tom Vilsack. “That mission will guide us as this important first step launches a broader initiative to reduce Salmonella illnesses associated with poultry in the U.S.”

“Today’s announcement is an important moment in U.S. food safety because we are declaring Salmonella an adulterant in a raw poultry product,” said Sandra Eskin, USDA Deputy Under Secretary for Food Safety. “This is just the beginning of our efforts to improve public health.”

By declaring Salmonella an adulterant in these products, FSIS will be able to ensure that highly contaminated products that could make people sick are not sold to consumers. Since 1998, breaded and stuffed raw chicken products have been associated with up to 14 outbreaks and approximately 200 illnesses. Products in this category are found in the freezer section and include some chicken cordon bleu or chicken Kiev products. These products appear cooked, but they are heat-treated only to set the batter or breading and the product contains raw poultry. Continual efforts to improve the product labeling have not been effective at reducing consumer illnesses.

Leave a comment

Posted in Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, microbial contamination, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Microbiology Risk, Research, Salmonella, Salmonella in Chicken

Research – English E. coli outbreak caused by milk pasteurisation problem in 2019

Posted on August 3, 2022 by | Leave a comment

Cambridge Org

In November 2019, an outbreak of Shiga toxin-producing Escherichia coli O157:H7 was detected in South Yorkshire, England. Initial investigations established consumption of milk from a local dairy as a common exposure. A sample of pasteurised milk tested the next day failed the phosphatase test, indicating contamination of the pasteurised milk by unpasteurised (raw) milk. The dairy owner agreed to immediately cease production and initiate a recall. Inspection of the pasteuriser revealed a damaged seal on the flow divert valve.

Ultimately, there were 21 confirmed cases linked to the outbreak, of which 11 (52%) were female, and 12/21 (57%) were either <15 or >65 years of age. Twelve (57%) patients were treated in hospital, and three cases developed haemolytic uraemic syndrome. Although the outbreak strain was not detected in the milk samples, it was detected in faecal samples from the cattle on the farm. Outbreaks of gastrointestinal disease caused by milk pasteurisation failures are rare in the UK. However, such outbreaks are a major public health concern as, unlike unpasteurised milk, pasteurised milk is marketed as ‘safe to drink’ and sold to a larger, and more dispersed, population. The rapid, co-ordinated multi-agency investigation initiated in response to this outbreak undoubtedly prevented further cases.

Leave a comment

Posted in E.coli O157, E.coli O157:H7, food bourne outbreak, Food Illness, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Food Poisoning, Foodborne Illness, foodborne outbreak, foodbourne outbreak, Illness, microbial contamination, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Microbiology Risk, outbreak, STEC, STEC E.coli

Argentina – Botulism case prompts warning in Argentina

Posted on August 3, 2022 by | Leave a comment

Food Safety News

kswfoodworld

Argentinian officials have warned people not to consume a specific product line due to the risk of botulism.

The National Administration of Drugs, Foods and Medical Devices (ANMAT) said a suspected case of botulism has been associated with a product of the A Pleno brand, produced in Villa de las Rosas.

No official details were given about the sick person but local station Radio Verdad was told the patient was 47-years old and remained in the hospital in a serious condition after eating an expired A Pleno product.

The General Directorate of Control of the Food Industry in Córdoba and agencies in the areas of Villa de las Rosas and Villa Dolores are involved in the investigation.

ANMAT advised people not to eat any A Pleno branded products, which include peanut butter and cheese spread alternatives, and told traders to stop selling them.

Another outbreak in Argentina in Misiones earlier this year affected up to 18 people with two deaths. It was linked to homemade sausages made from wild animal meat that were shared in the community.

Leave a comment

Posted in Clostridium, Clostridium botulinum, food contamination, food handler, Food Hazard, Food Hazrd, Food Hygiene, Food Illness, Food Inspections, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Food Pathogen, Food Poisoning, food recall, Food Safety, Food Safety Alert, Food Testing, Food Toxin, Foodborne Illness, Illness, microbial contamination, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Microbiology Risk

Research – Thermal inactivation of Salmonella enterica and nonpathogenic bacterial surrogates in wheat flour by baking in a household oven 

Posted on August 2, 2022 by | Leave a comment

Journal of Food Protection

Wheat flour has been implicated in recalls and outbreaks linked to Salmonella and pathogenic Escherichia coli. An instructional online video posted on a popular YouTube channel with over 20 million subscribers claimed that safe raw cookie dough could be made from flour baked in a household oven at 177°C (350°F) for 5 min but no evidence in support of that claim was provided. This study was conducted to assess thermal inactivation of two Salmonella strains, as well as Enterobacter aerogenes and Pantoea dispersa in wheat flour during home oven style baking. Wheat flour was inoculated with Salmonella Enteritidis PT 30, Salmonella Typhimurium PT 42 or their potential surrogates at high concentrations (4.8-6.1 log CFU/g) before baking in consumer-style convection oven (toaster oven) at 149, 177, and 204°C (300, 350, or 400°F) for up to 7 min. Flour was heated in aluminum tray with a maximum depth of ~2 cm. Heated wheat flour samples (5 g each) were enumerated in triplicate, and microbial concentration was expressed in log CFU/g. Thermal profiles of the geometric center of the wheat flour pile and air in the oven during the baking were recorded. Water activity of wheat flour samples was also measured before and after baking. Water activity of wheat flour decreased as baking temperature and time increased. Water activity values ranged from 0.30 to 0.06 after 7 min as oven temperature increased from 149 to 204°C. Thermal inactivation kinetics were linear until counts approached the limit of detection for all microorganisms. D-values for Salmonella and potential surrogate strains ranged from 1.86 to 2.13 min at 149°C air temperature, 1.66 to 1.92 min at 177°C air temperature, and 1.12 to 1.38 min at 204°C air temperature. Both Salmonella strains and surrogates showed similar inactivation patterns. Baking of wheat flour in household toaster ovens has potential as an inactivation treatment of pathogenic bacteria in consumer homes, despite its low water activity.

Leave a comment

Posted in Decontamination Microbial, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, microbial contamination, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Microbiology Risk, Research, Salmonella

Research – Terpenes Combinations Inhibit Biofilm Formation in Staphyloccocus aureus by Interfering with Initial Adhesion

Posted on August 1, 2022 by | Leave a comment

MDPI

Staph

The biofilm is a conglomerate of cells surrounded by an extracellular matrix, which contributes to the persistence of infections. The difficulty in removing the biofilm drives the research for new therapeutic options. In this work, the effect of terpenes (−)-trans-Caryophyllene, (S)-cis-Verbenol, (S)-(−)-Limonene, (R)-(+)-Limonene, and Linalool was evaluated, individually and in combinations on bacterial growth, by assay with resazurin; the formation of biofilm, by assay with violet crystal; and the expression of associated genes, by real-time PCR, in two clinical isolates of Staphyloccocus aureus, ST30-t019 and ST5-t311, responsible for more than 90% of pediatric infections by this pathogen in Paraguay. All combinations of terpenes can inhibit biofilm formation in more than 50% without affecting bacterial growth. The most effective combination was (−)-trans-Caryophyllene and Linalool at a 500 μg/mL concentration for each, with an inhibition percentage of 88%. This combination decreased the expression levels of the sdrD, spa, agr, and hld genes associated with the initial cell adhesion stage and quorum sensing. At the same time, it increased the expression levels of the cap5B and cap5C genes related to the production of capsular polysaccharides. The combinations of compounds tested are promising alternatives to inhibit biofilm formation in S. aureus. View Full-Text

Leave a comment

Posted in Biofilm, Decontamination Microbial, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Food Technology, microbial contamination, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Microbiology Risk, Research, Staphylococcus aureus

Research – Prevalence, genomic characterization, and risk assessment of human pathogenic Vibrio species in seafood

Posted on August 1, 2022 by | Leave a comment

Journal of Food Protection

Pathogenic Vibrio spp. are largely responsible for human diseases caused through consumption of contaminated seafood. The aim of this study was to determine the prevalence, population densities, species diversity and molecular characteristics of pathogenic Vibrio in various seafood commodities and its associated health risks. Samples of finfish and shellfish (oysters and sea urchins) were collected from different regions and analyzed for Vibrio using the Most Probable Number (MPN) technique. Genomic DNA of putative Vibrio isolates was analyzed by whole genome sequencing (WGS) for taxonomic identification and identification of genes responsible for virulence and antimicrobial resistance. The risk of vibrio-related illnesses due to the consumption of contaminated seafood was assessed using Risk Ranger. Population densities of presumptive Vibrio fell in the range of 2.6 – 4.4 Log MPN/g and correlated with seasonality, with the summer season favoring significantly (p < 0.05) higher Vibrio counts. A total of 15 Vibrio isolates were identified as V. alginolyticus (5), V . parahaemolyticus (6), V. harveyi (2) or V. diabolicus (2). Two of the six V. parahaemolyticus isolates (ST 2504 and ST 2505) originating from oysters were found to be either tdh + or trh + and thus considered a human pathogen due to elaboration of Thermostable Direct Hemolysin (TDH) or TDH-related hemolysin (TRH). In addition to virulence genes, the shellfish isolates also harbored genes encoding resistance to multiple antibiotics including tetracycline, penicillin, quinolone and beta-lactam antibiotics, thus arousing concern. The risk assessment exercise pointed to an estimated 21 annual cases of V. parahaemolyticus -associated gastroenteritis in the general population attributed to consumption of contaminated oysters. This study highlights not only the wide prevalence and diversity of Vibrio in seafood, but also the potential of certain strains to threaten public health.

Leave a comment

Posted in Decontamination Microbial, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, microbial contamination, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Microbiology Risk, Vibrio, Vibrio albensis, Vibrio alginolyticus, Vibrio cholera, vibrio cholerae, Vibrio parahaemolyticus, Vibrio vulnificans, Vibrio vulnificus

Research – Listeria monocytogenes Pathogenesis: The Role of Stress Adaptation

Posted on July 31, 2022 by | Leave a comment

MDPI

Adaptive stress tolerance responses are the driving force behind the survival ability of Listeria monocytogenes in different environmental niches, within foods, and ultimately, the ability to cause human infections. Although the bacterial stress adaptive responses are primarily a necessity for survival in foods and the environment, some aspects of the stress responses are linked to bacterial pathogenesis. Food stress-induced adaptive tolerance responses to acid and osmotic stresses can protect the pathogen against similar stresses in the gastrointestinal tract (GIT) and, thus, directly aid its virulence potential. Moreover, once in the GIT, the reprogramming of gene expression from the stress survival-related genes to virulence-related genes allows L. monocytogenes to switch from an avirulent to a virulent state. This transition is controlled by two overlapping and interlinked transcriptional networks for general stress response (regulated by Sigma factor B, (SigB)) and virulence (regulated by the positive regulatory factor A (PrfA)). This review explores the current knowledge on the molecular basis of the connection between stress tolerance responses and the pathogenesis of L. monocytogenes. The review gives a detailed background on the currently known mechanisms of pathogenesis and stress adaptation. Furthermore, the paper looks at the current literature and theories on the overlaps and connections between the regulatory networks for SigB and PrfA.

Leave a comment

Posted in Decontamination Microbial, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Listeria, Listeria monocytogenes, microbial contamination, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Microbiology Risk, Research

Research – Chinese Foodborne Botulism Outbreaks Have High Mortality Rate; Tofu, Beef Common Causes

Posted on July 31, 2022 by | Leave a comment

Food Safety Magazine

A study published in China CDC Weekly provides insight into foodborne botulism outbreaks in China. Researchers conducted an epidemiological analysis for the years of 2004–2020, which revealed a high mortality rate for cases of foodborne botulism and informed recommendations for reducing such outbreaks in China.

In the epidemiological analysis, data was collected from 22 of 31 Chinese provincial-level administrative divisions (PLADs) of the National Foodborne Disease Outbreaks Surveillance system, as well as the China National Knowledge Infrastructure, Wanfang Data, and Chinese Science and Technique Journals. The number and proportion of foodborne botulism outbreaks, illnesses, and deaths by PLAD; food types associated with outbreaks; and contributing factors were observed.

In total, 80 foodborne botulism outbreaks occurred in China during 2004−2020, with 386 illnesses and 55 deaths; initial misdiagnosis occurred in 27.5 percent of botulism cases. Most outbreaks were reported between June and August, aside from a spike in cases in January. Of the 22 PLADs that reported foodborne botulism outbreaks, Xinjiang reported the largest number of outbreaks (20), followed by Qinghai (13). Home-cooked, traditionally processed stinky tofu and dried beef were the most common vehicles for Clostridium botulinum, linked to 51.25 percent of botulism cases. Improper processing and storage practices contributed to 77.5 percent of foodborne botulism outbreaks.

Based on the study’s findings, the researchers suggest the implementation of botulism prevention and food safety education for farmers and herders in Xinjiang and Qinghai. The researchers also stress the urgency of improving Chinese foodborne illness outbreak investigation.

Leave a comment

Posted in Bacterial Toxin, Clostridium, Clostridium botulinum, food bourne outbreak, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Food Safety, Food Safety Alert, Food Safety Management, food safety training, Food Toxin, foodborne outbreak, foodbourne outbreak, microbial contamination, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Microbiology Risk, outbreak

Research – Peroxyacetic Acid Effectiveness against Salmonella on Raw Poultry Parts is not Affected by Organic Matter

Posted on July 31, 2022 by | Leave a comment

Journal of Food Protection

Organic matter (OM) accumulation is common in chill tanks used to decontaminate raw poultry parts during processing. Organic matter negatively affects the antimicrobial activity of chlorine-based compounds, but its effect on the antimicrobial effectiveness of peroxyacetic acid (PAA) on poultry meat has not been described. Therefore, this study evaluated the effect of OM on the efficacy of PAA solutions in simulated post-chill tanks to reduce Salmonella artificially inoculated onto chicken parts. Chicken thighs were inoculated with a five-strain cocktail of poultry-borne Salmonella enterica serovars at ca. 6 log10CFU/ml. Then, the thighs were immersed for 30 or 45 s in PAA solutions (500 or 1,000 ppm) with chicken slurry to simulate OM accumulation (0, 15 or 30 g/L). The thighs were rinsed with neutralizing buffered peptone water (100 ml) and rinsates were plated onto XLD agar. Experiments were performed in triplicate (3 thighs/treatment/replicate). Chemical oxygen demand (COD), total nitrogen (TN), and pH were measured as the water quality parameters of the PAA solutions before and after use. COD ranged from 2,905 mg/L in unused 500-ppm solutions without added OM to 6,290 mg/Lin used 1,000-ppm solutions with 30 g/L of OM. Initial TN was 42.5 ± 2.0 mg/L and 60.9 ± 8.3 mg/L for 15 and 30 g/L OM, which increased by 27 ± 17 mg/L after use. The pH of solutions ranged from 3.16 ± 0.14 to 3.42 ± 0.09 for the 1,000-ppm solutions and from 3.59 ± 0.06 to 3.96 ± 0.06 for the 500-ppm solutions. Mean Salmonella reductions were 0.9 ± 0.1 log10CFU/ml of rinsate for the 500-ppm PAA treatment and 1.1 ± 0.1 log10CFU/ml of rinsate for 1,000-ppm PAA treatment. Exposure time did not have a significant effect on the logarithmic reductions. There was no significant effect of OM concentration (p>0.05) on the reductions, indicating that the antimicrobial efficacy was not affected and that PAA solutions may continue to be reused as long as the PAA concentration is actively monitored.

Leave a comment

Posted in Decontamination Microbial, Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, microbial contamination, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Microbiology Risk, Research, Salmonella, Salmonella in Chicken

Research – Investigating and Preventing Foodborne Outbreaks Linked to Raw Milk and Raw Milk Dairy Products

Posted on July 30, 2022 by | Leave a comment

NY Food Safety

Foodborne disease outbreaks and cases linked to raw milk and raw milk dairy products continue to be a concern. Investigations of these outbreaks often represent unique challenges, such as patients who may not be willing to disclose the source of the raw milk or identifying appropriate samples to collect on potential source farms (do you know what “milk socks” are and where to find them?)

To learn more about raw milk and dairy products, how to investigate outbreaks linked to them, and how to help prevent these outbreaks, view the NY CoE webinar on “Investigating and preventing foodborne disease outbreaks linked to raw milk and raw milk dairy products”, presented by Dr. Martin Wiedmann from Cornell University on 6/2/2022. Following the presentation, a panel of individuals who have been involved with investigating raw milk outbreaks participated in a Q&A dialogue. Panelists included subject matter experts from the New York State Department of Health, New York State Department of Agriculture and Markets, Maine Department of Health and Human Services, and Pennsylvania Department of Public Health. The webinar was recorded and can be accessed on the NY CoE YouTube here.

Leave a comment

Posted in Food Micro Blog, Food Microbiology, Food Microbiology Blog, Food Microbiology Research, Food Microbiology Testing, Food Safety, Food Safety Management, food safety training, microbial contamination, Microbiological Risk Assessment, Microbiology, Microbiology Investigations, Microbiology Risk