Category Archives: Food Microbiology Research

Kenya – Mukumu girls deaths linked to E.coli, Salmonella from contaminated water

KBC

Three students and a teacher at Sacred Heart Mukumu Girls in Kakamega died as a result of contaminated water.

The Ministry of Health Friday said preliminary findings had revealed E. coli and Salmonella typhi, a bacterium that is responsible for typhoid fever as the causes of the illness initially suspected to be cholera.

“The Ministry wishes to inform the general public that this disease is likely to be a mixture of E. coli and Salmonella typhi which usually occurs if water sources are contaminated with these micro-organisms” Ag. Director General for Health Dr. Patrick Amoth said.

A comprehensive investigation is however underway even as the top health official ruled out aflatoxin.

Several learning institutions including, Mukumu Girls and Butere Boys in Kamamega and the latest being Mukuuni Boys High School in Chuka, Tharaka Nithi County have been closed after students were taken ill.

“The Ministry of Health has taken several water, food, and human tissue samples, from which preliminary laboratory investigations undertaken have revealed Enterotoxigenic E. coli and Salmonella typhi as the causes of the illness,” he said

“Further laboratory investigations carried out on the grains and pulses for aflatoxin have turned negative for aflatoxicosis- a dangerous fungal infection from poorly stored cereal grains” he added.

Research – Montana Raw Water Campylobacter Outbreak Linked to Bird’s Nest

Food Poisoning Bulletin

A Montana raw water Campylobacter outbreak in 2022 has been linked to a bird’s nest in a concrete cache from Kennedy Creek, according to ARS Technica. Nineteen people were sickened in that outbreak, and one person was hospitalized.

Research – Salmonella and Flour

Food Poisoning News

Salmonella has struck again with a recent multistate outbreak spanning eleven states, resulting in at least a dozen ill including three requiring hospitalization. The CDC has identified raw flour as the culprit, but are still trying to pinpoint which brand(s). The sources of these victims’ illnesses have been identified as both raw dough and batter, with the only common denominator in these consumed products being raw flour.

Baked/fully cooked flour isn’t an issue, but the problem is that many people consume flour raw by eating cookie dough or batter before cooking it. Although it can be fun to “try a little on your finger” before it goes into the oven and has a chance to cook, this is an inherently dangerous practice. The flour in these uncooked products is raw, which means it hasn’t been treated for bacteria yet (one way to “treat” food is to heat it to a sufficient temperature, as is done with cakes and cookies). Cooking the product eliminates the bacteria, therefore drastically reducing the chance of becoming ill.

This is why it is extremely important that when making these types of foods that consumers follow the instructions for how high the temperature needs to be when cooking, and for how long a product needs to bake. Thee instructions aer both to provide a well-cooked product, but also for safety. These directions are on the packaging to ensure that your food isn’t undercooked, which is a strong contributor to illness.

Research – Norwegian raw cow`s milk, a potential source of zoonotic pathogens?

NMBU

The worldwide emerging trend of eating “natural” foods, that has not been processed, also applies for beverages. According to Norwegian legislation, all milk must be pasteurized before commercial sale but drinking milk that has not been heat-treated, is gaining increasing popularity.
Scientist are warning against this trend and highlights the risk of contracting disease from milk-borne microorganisms. To examine potential risks associated with drinking unpasteurized milk in Norway, milk-and environmental samples were collected from dairy farms located in south-east of Norway. The samples were analyzed for the presence of specific zoonotic pathogens; Listeria monocytogenes, Campylobacter spp., and Shiga toxin-producing Escherichia coli(STEC).
Cattle are known to be healthy carriers of these pathogens, and Campylobacter spp. and STEC have a low infectious dose, meaning that infection can be established by ingesting a low number of bacterial cells. L. monocytogenes causes one of the most severe foodborne zoonotic diseases, listeriosis, that has a high fatality rate. All three pathogens have caused milk borne disease outbreaks all over the world, also in Norway. During this work, we observed that the prevalence of the three examined bacteria were high in the environment at the examined farms. In addition, 7% of the milk filters were contaminated by STEC, 13% by L. monocytogenes and 4% by Campylobacter spp. Four of the STEC isolates detected were eae-positive, which is associated with the capability to cause severe human disease. One of the eae-positive STEC isolates were collected from a milk filter, which strongly indicate that Norwegian raw milk may contain potential pathogenic STEC.
To further assess the possibilities of getting ill by STEC after consuming raw milk, we examined the growth of the four eae-positive STEC isolates in raw milk at different temperatures. All four isolates seemed to have ability to multiply in raw milk at8°C, and one isolate had significant growth after 72 hours. Incubation at 6°C seemed to reduce the number of bacteria during the first 24 hours before cell death stopped.
These findings highlight the importance of stable refrigerator temperatures, preferable <4°C,for storage of raw milk. The L. monocytogenes isolates collected during this study show genetic similarities to isolates collected from urban and rural environmental locations, but different clones were predominant in agricultural environments compared to clinical and food environments. However ,the results indicate that the same clone can persist in a farm over time, and that milk can be contaminated by L. monocytogenes clones present in farm environment.
Despite testing small volumes(25mL) of milk, we were able to isolate both STEC and Campylobacter spp. directly from raw milk. A proportion of 3% of the bulk tank milk and teat milk samples were contaminated by Campylobacter spp. and one STEC was isolated from bulk tank milk. L monocytogenes was not detected in bulk tank milk, nor in teat milk samples. The agricultural evolvement during the past decades have led to larger production units and new food safety challenges.
Dairy cattle production in Norway is in a current transition from tie-stall housing with conventional pipeline milking systems, to modern loose housing systems with robotic milking. The occurrence of the three pathogens in this project were higher in samples collected from farms with loose housing compared to those with tie-stall housing. Pasteurization of cow’s milk is a risk reducing procedure to protect consumers from microbial pathogens and in most EU countries, commercial distribution of unpasteurized milk is legally restricted. Together, the results presented in this thesis show that the animal housing may influence the level of pathogenic bacteria in the raw milk and that ingestion of Norwegian raw cow’s milk may expose consumers to pathogenic bacteria which can cause severe disease, especially in children, elderly and in persons with underlying diseases. The results also highlight the importance of storing raw milk at low temperatures between milking and consumption.

Research – Enterohemorrhagic Escherichia coli O157:H7 — Xuzhou City, Jiangsu Province, China, 2001–2021

China CDC

  • Summary

    What is already known about this topic?The largest and longest outbreak of diarrhea, which was complicated with hemolytic uremic syndrome (HUS) caused by enterohemorrhagic Escherichia coli (EHEC) O157:H7, occurred in Xuzhou City and its adjacent areas from 1999 to 2000 in China.

    What is added by this report?According to surveillance results from 2001 to 2021, there was a significant decrease in the isolation rate of O157:H7, and cattle and sheep remained the primary hosts. However, non-Shiga toxin-producing O157:H7 emerged as the dominant strain, with stx2+stx1– strains following closely behind.

    What are the implications for public health practice?National surveillance of O157:H7 effectively serves as an early warning system and guidance for assessing the intensity and trend of disease epidemics. It is crucial to raise awareness of the public health risks associated with Shiga toxin-producing E. coli.

Research – Classification and ranking of shigatoxin-producing Escherichia coli (STEC) genotypes detected in food based on potential public health impact using clinical data

Science Direct

Abstract

Risk classification and management of shigatoxin-producing E. coli (STEC) isolated from food has been hampered by gaps in knowledge about the properties that determine the extent to which different subtypes of STEC can cause severe disease. Data on the proportion of infected human cases being affected by severe illness enables an evaluation of existing approaches for classifying STEC strains and the development of a new public health based approach. Evaluations show that existing approaches do not unequivocally classify different STEC variants according to their ability to cause severe disease. A new approach for ranking of STEC genotypes, combining the estimated probability of the strain to cause severe illness with the public health burden associated with the illness in terms of DALY per case, address these limitations. The result is a list of STEC genotypes in descending order of potential public health burden per case. The approach is risk based in considering the probability and consequences following infection (severe illness), and can support transparent risk management. This is illustrated by, arbitrarily, separating the ranked list of genotypes into classes based on the potential public health burden, and by characterising collections of strains isolated from different foods into different classes. Further, the classification of food samples as satisfactory or not based on the cost in terms of proportion of food being rejected and the benefit in terms of the proportion of strains causing severe illness (HUS) that are being captured is demonstrated using this approach.

Research – Raw food: health risks are often underestimated

BFR

A glass of raw milk for breakfast, a roll with raw ham in the lunch break and a homemade smoothie with frozen berries in the afternoon – raw or unheated food is a regular part of the population’s menu. This is shown by a current, representative survey by the Federal Institute for Risk Assessment ( BfR ). Raw animal and vegetable products should be consumed with caution. They can contain pathogenic germs such as salmonella, listeria and campylobacter and lead to foodborne infections. Small children, people with previous illnesses, the elderly and pregnant women are particularly at risk. “The health risks of raw foods are often underestimated,” says BfR-President Professor Dr. dr Andrew Hensel. “Heating protects. Diseases can be avoided with simple kitchen hygiene rules. Sensitive groups of people in particular should only eat raw animal food that has been sufficiently heated.”

To the BfR Consumer Monitor Special information brochure, raw foods:

The particularly popular raw foods include raw sausage and raw ham, which are eaten several times a week by more than a third of those surveyed. At least one to three times a month, 73 percent of those surveyed eat raw meat and sausage products, followed by soft cheese made from raw milk (57 percent). Other foods eaten with the same frequency by around a third of those surveyed are raw meat (38 percent), cold-smoked fish (33 percent) and frozen berries (33 percent). While about one in five (21 percent) eats raw sweet dough with eggs at least once or three times a month, it is still one in eight (12 percent) when it comes to raw dough without eggs. 19 percent of respondents drink raw milk at least one to three times a month.

Every year around 100,000 diseases are reported in Germany that may have been caused by bacteria, viruses or parasites in food. The number of unreported cases is likely to be much higher. While salmonella, listeria and norovirus are known to the majority of the population, the knowledge about other food-related pathogens is less good. Particularly surprising: Although campylobacteriosis has been the most frequently reported bacterial food-borne illness in Germany and Europe for years, only just under a quarter (23 percent) of people know the causative pathogen Campylobacter . The same applies to the abbreviations STEC, EHEC and VTEC for particularly dangerous Escherichia coli-Bacteria (27 percent). The pathogens mentioned can lurk in a large number of raw foods: salmonella and campylobacter in poultry, chicken eggs and raw meat and sausage products, listeria in cold-smoked fish products and raw milk cheese or noroviruses in raw oysters and frozen berries as well as STEC in flour.

The perception of the health risk sometimes differs greatly between different raw or unheated foods. The majority of respondents see a medium to (very) high health risk in particular with raw fish and raw seafood, raw meat, raw eggs and raw sweet dough with eggs. Frozen berries, on the other hand, are perceived as the least risky. Other foods that the majority of those surveyed also associate with a (very) low health risk are soft cheese made from raw milk, cold-smoked fish, raw sausage and raw ham, as well as raw dough without eggs.

In order to protect yourself from foodborne infections, it is important to observe the rules of kitchen hygiene so that pathogens do not spread from raw foods to others. Small children, pregnant women and people with a weakened immune system should only eat raw food from animals if they have been sufficiently heated beforehand.

Via the BfR consumer monitor

Whether antibiotic resistance, microplastics, salmonella or aluminum in food – which health risks are known to the population and what worries them? The BfR Consumer Monitor, a representative population survey that has been carried out regularly since 2014, provides answers to these and other questions . To this end, around 1,000 people living in private households in Germany are being interviewed by telephone on behalf of the BfR . In addition, the BfR conducts representative surveys on individual topics that are of particular current interest, such as tattoos, e-cigarettes, superfoods or additives in food.

Research Imported spring onions related to the first recorded outbreak of enteroinvasive Escherichia coli in Denmark, November to December 2021

Eurosurveillance

Enteroinvasive  (EIEC) is a Gram-negative bacteria causing diarrhoeal disease. EIEC is transmitted via the faecal–oral route, with a usual incubation period of 1–3 days; infections are frequently related to contaminated food and water [1,2]. In Denmark, disease caused by EIEC is mostly observed in returning travellers, but secondary transmission from person-to-person may occur [3]. In Europe, outbreaks of EIEC in 2012, 2014 and 2017 have been reported and, for all of these, contaminated vegetables were suspected as the source [46].

Clinically, EIEC infections present either with watery diarrhoea or dysentery. EIEC invade the epithelial cells of the large intestine in the same manner as  and symptoms resulting from EIEC infection are clinically indistinguishable from shigellosis [7]. Studies have shown that  and  species have high genomic and phenotypic similarity, leading to propose that  species should be reclassified as a subspecies of  [8,9].

Diagnostics of EIEC in Denmark are done locally through 10 different clinical microbiology laboratories situated at hospitals in the five Danish regions. The criteria for carrying out an EIEC diagnostic vary. Some laboratories test all faecal samples for diarrhoeagenic  including EIEC, while others test only faecal samples from suspected patients, based on their age, travel history and presence of bloody diarrhoea. The PCR diagnostic assays target the invasive plasmid gene () shared by both  spp. and EIEC [10]. Culture is required to differentiate the two species, and if culture is not possible or unsuccessful, faecal specimens are considered positive for the combination /EIEC. Detection of /EIEC is voluntarily notified as part of the Danish laboratory surveillance, where episodes are irregularly reported by the clinical microbiology laboratories to Statens Serum Institut (SSI), the national public health institute. All isolates from successfully cultured samples are furthermore routinely sent on a voluntary basis to SSI for further characterisation.

Outbreak detectionOn 10 December 2021, the clinical microbiology laboratory at Slagelse hospital in Region Zealand reported observing an increase between 5 and 8 December of patients diagnosed with domestically-acquired EIEC. During this period, this laboratory had detected a total of five such patients. On the same day (10 December), SSI identified one EIEC isolate with serotype O96:H- and three with serotype O136:H7 (two of which originated from Slagelse hospital), the latter a type never found in human samples from Denmark before. In total, between 6 and 10 December, SSI had received six EIEC isolates from three different regions of Denmark, exceeding the total number of EIEC isolates that were received in the months of December of the 2 previous years. A national outbreak was therefore declared on 13 December.

Research – BSI – What is PAS 320 Developing and sustaining a mature food safety culture – Guide about?

BSI

When it comes to food safety, the common factor in many incidents and recalls is people. In response PAS 320:2023 gives organizations clear guidance on what a good food safety culture looks like.

Who is PAS 320 Developing and sustaining a mature food safety culture – Guide for?

Any organization of any size or purpose across the food chain, from primary production to final delivery to consumers. PAS 320:2023 might also be of use to:

  • Educational institutions
  • Trade associations
  • Coalitions of action
  • Professional bodies
  • Certification and accreditation bodies
  • Certification programme owners (CPOs) and regulatory bodies

What does PAS 320 Developing and sustaining a mature food safety culture – Guide cover?

PAS 320:2023 gives guidance on recognizing and maintaining a positive culture of food safety in any food organization, regardless of its size or focus.

It includes guidance on using a food safety culture maturity model against which organizations can assess their level of maturity to help foster cultural change that impacts on all functions and levels in a food organization. It covers the defined pre-requisites and taxonomy of organizational culture, with a food safety culture focus. Why should you use PAS 320 Developing and sustaining a mature food safety culture – Guide?

  • It provides practical guidance on recognizing and maintaining a positive safety culture in any food organization
  • It will drive best practices throughout the industry that can proactively mitigate food safety risks by embedding a safety culture in food organizations, top down and bottom up

It can help increase confidence in food organizations and strengthen their risk management.

PAS 320:2023 contributes to UN Sustainable Development Goal 2 on ending hunger, and achieving food security and sustainable agriculture, and Goal 3 on good health and well-being.

Research – Sanitizers to reduce Salmonella on and in turkey eggs evaluated

Feedstuffs

hazegg.jpg

USPOULTRY and the USPOULTRY Foundation have announced the completion of a funded research project at Cargill Inc., in which researchers evaluated egg wash sanitizers to reduce Salmonella contamination on and in turkey eggs. The research was made possible in part by an endowing Foundation gift from Cargill and proceeds from the International Poultry Expo, part of the International Production & Processing Expo (IPPE).

According to the research summary, Salmonella remains the number one cause of foodborne illness in the U.S., which causes an economic burden for the poultry industry as well as public concern for the consumers. As such, the poultry industry must be diligent during processing to reduce Salmonella risk, including interventions for hatch eggs.

Dr. Ted Brown and colleagues at Cargill, Inc. recently completed a research project that evaluated sanitizers with thymol, peracetic acid (PAA), bromine, peroxide, chlorine and quaternary ammonium. The peroxide product proved to be the most effective egg sanitizer at reducing Salmonella prevalence on the egg surface by more than 73%. None of the sanitizers tested in the trial caused damage to the cuticle, and Salmonella did not penetrate the egg.