Category Archives: Microbiology

Research – Surveillance of Human Cases of Salmonellosis, Campylobacteriosis, Listeriosis, and Hepatitis A in Campania (Southern Italy): Seven-Year Monitoring (2013–2019)

MDPI

Abstract

Foodborne infections cause illness and death every year worldwide. The aim of this study was to describe trends in 2013–2019 in the occurrence of human cases of salmonellosis, campylobacteriosis, listeriosis, and hepatitis A in the Campania region. Human case data were provided by the National Surveillance System of disease and were grouped by year, province, age group, and sex. Moreover, the number of people hospitalized was recorded. In the Campania region, the total number of confirmed human cases for the diseases investigated was 1924, with Hepatitis A and the Salmonellosis as the first most reported (1009 and 825 cases, respectively). The incidence rates of gastroenteritis under study were lower than those in Italy and European Union in the same period, with the exception of Hepatitis A whose incidence was higher than that recorded in Italy. Data on hospitalizations pointed out the onset of severe forms of infection also for listeriosis and campylobacteriosis, whose incidence was very low (27 and 63 cases, respectively). Unfortunately, no information on the foods implicated is available. Although probably underestimated, gastroenteritis due to foodborne agents still represents a burden in Campania, and continuous monitoring and implementation of the currently available regional surveillance system is required.

Research – Advances in science and risk assessment tools for Vibrio parahaemolyticus and V. vulnificus associated with seafood: meeting report

WHO

Globally, the Vibrio parahaemolyticus and Vibrio vulnificus represent important human pathogens associated with the consumption of seafood. In response to the requests for scientific advice from Codex Committee on Food Hygiene (CCFH), risk assessments for the pathogens V. vulnificus, V. cholerae, V. parahaemolyticus and guidance on methods for the detection of Vibrio spp. with seafood have been conducted and published previously by JEMRA. In order to provide an update on the state-of-the-art advice regarding risk assessment for V. parahaemolyticus and V. vulnificus in seafood, an expert meeting was convened.

Several critical developments in the last decade were subsequently noted by the expert working group: 1) The emergence of highly pathogenic strains; 2) In response to climate change, there has been a significant geographical spread regarding when and where these seafood-associated Vibrio infections; 3) Demographic considerations are very important; 4) A range of new approaches for best practice; and 5) A range of new methods, such as those utilising genomics and satellite imagery. This report describes the output of that expert meeting.

Research – Bacterial pathogens and climate change

The Lancet

Read the full article at the link above

A systematic analysis of the literature showed that 58% of infectious diseases in humans have been aggravated at some point by climatic hazards, such as changes in temperatures and water and food availability.

The leading pathogens responsible (eg, S aureus, E coli, K pneumoniae, S pneumoniae, and non-typhoidal Salmonella) have all been found to have climate-dependent reactions, causing an increase in their diffusion and even resistance to treatment.

 For example, sharp temperature decreases have been associated with an increased incidence of pneumonia, and increased morbidity in cold and humid weather.

 

Research -Control measures for Shiga toxin-producing Escherichia coli (‎STEC)‎ associated with meat and dairy products: meeting report

WHO

Although Shiga toxin-producing Escherichia coli (STEC) have been isolated from a variety of food production animals, they are most commonly associated with ruminants from which we derive meat and milk. Because of the widespread and diverse nature of ruminant-derived food production, coupled with the near ubiquity of STEC worldwide, there is no single definitive solution for controlling STEC that will work alone or in all situations. Instead, the introduction of multiple interventions applied in sequence, as a “multiple-hurdle scheme” at several points throughout the food chain (including processing, transport and handling) will be most effective.

This report summarizes the review and evaluation of interventions applied for the control of STEC in cattle, raw beef and raw milk and raw milk cheese manufactured from cows’ milk, and also evaluates available evidence for other small ruminants, swine and other animals. The information is presented from primary production, to the end of processing, providing the reader with information on the currently available interventions based on the latest scientific evidence.

This work was undertaken to support the development of guidelines for the control of STEC in beef, raw milk and cheese produced from raw milk by the Codex Committee on Food Hygiene (CCFH).

Research – Listeria monocytogenes—How This Pathogen Uses Its Virulence Mechanisms to Infect the Hosts

MDPI

Abstract

Listeriosis is a serious food-borne illness, especially in susceptible populations, including children, pregnant women, and elderlies. The disease can occur in two forms: non-invasive febrile gastroenteritis and severe invasive listeriosis with septicemia, meningoencephalitis, perinatal infections, and abortion. Expression of each symptom depends on various bacterial virulence factors, immunological status of the infected person, and the number of ingested bacteria. Internalins, mainly InlA and InlB, invasins (invasin A, LAP), and other surface adhesion proteins (InlP1, InlP4) are responsible for epithelial cell binding, whereas internalin C (InlC) and actin assembly-inducing protein (ActA) are involved in cell-to-cell bacterial spread. L. monocytogenes is able to disseminate through the blood and invade diverse host organs. In persons with impaired immunity, the elderly, and pregnant women, the pathogen can also cross the blood–brain and placental barriers, which results in the invasion of the central nervous system and fetus infection, respectively. The aim of this comprehensive review is to summarize the current knowledge on the epidemiology of listeriosis and L. monocytogenes virulence mechanisms that are involved in host infection, with a special focus on their molecular and cellular aspects. We believe that all this information is crucial for a better understanding of the pathogenesis of L. monocytogenes infection.

Research – Variability in Cold Tolerance of Food and Clinical Listeria monocytogenes Isolates

MDPI

Abstract

The aim of this study was to investigate the level of strain variability amongst food and clinical Listeria monocytogenes isolates growing at low temperatures (4 and 7 °C) in both laboratory media and real food matrices. Isolates (n = 150) grown in laboratory media demonstrated a large variation in growth profiles measured using optical density.
Overall, it was noted that clinical isolates exhibited a significantly higher growth rate (p ≤ 0.05) at 7 °C than the other isolates. Analysis of variance (ANOVA) tests of isolates grouped using Multi Locus Sequence Typing (MLST) revealed that clonal complex 18 (CC18) isolates were significantly (p ≤ 0.05) faster growing at 4 °C than other CC-type isolates while CC101, CC18, CC8, CC37 and CC14 were faster growing than other CC types at 7 °C. Euclidean distance and Ward method-based hierarchical clustering of mean growth rates classified 33.33% of isolates as faster growing.
Fast and slow growing representative isolates were selected from the cluster analysis and growth rates were determined using plate count data in laboratory media and model food matrices. In agreement with the optical density experiments, CC18 isolates were faster and CC121 isolates were slower than other CC types in laboratory media, UHT milk and fish pie. The same trend was observed in chocolate milk but the differences were not statistically significant. Moreover, pan-genome analysis (Scoary) of isolate genome sequences only identified six genes of unknown function associated with increased cold tolerance while failing to identify any known cold tolerance genes. Overall, an association that was consistent in laboratory media and real food matrices was demonstrated between isolate CC type and increased cold tolerance.

RASFF Alerts – Animal Feed – Salmonella – Fish Meal – Turkey Processed Protein – Rapeseed Meal

RASFF

Salmonella in fish meal from Poland in Lithuania

RASFF

Salmonella Muenster and Salmonella Rissen in turkey processed animal protein from Spain in Belgium

RASFF

Salmonella spp. in rapeseed meal from Germany in Finland, Denmark and Sweden

Research – Inhibition of Aflatoxin Production by Citrinin and Non-Enzymatic Formation of a Novel Citrinin-Kojic Acid Adduct

MDPI

Abstract

Screening for microorganisms that inhibit aflatoxin production from environments showed that Penicillium citrinum inhibited aflatoxin production by Aspergillus parasiticus. The inhibitory substance in the culture medium of P. citrinum was confirmed to be citrinin (CTN). RT-PCR analyses showed that CTN did not inhibit expressions of aflatoxin biosynthetic genes (aflRpksL1, and fas-1) of A. parasiticus, whereas feeding experiments using A. parasiticus showed that CTN inhibited the in vivo conversion of dihydrosterigmatocystin to AFB2·AFG2. These results suggest that CTN inhibits a certain post-transcriptional step in aflatoxin biosynthesis. CTN in the culture medium of A. parasiticus was found to be decreased or lost with time, suggesting that a certain metabolite produced by A. parasiticus is the cause of the CTN decrease; we then purified, characterized, and then analyzed the substance. Physico-chemical analyses confirmed that the metabolite causing a decrease in CTN fluorescence was kojic acid (KA) and the resulting product was identified as a novel substance: (1R,3S,4R)-3,4-dihydro-6,8-dihydroxy-1-(3-hydroxy-6-(hydroxymethyl)-4-oxo-4H-pyran-2-yl)-3,4,5-trimethyl-1H-isochromene-7-carboxylic acid, which was named “CTN-KA adduct”. Our examination of the metabolites’ toxicities revealed that unlike CTN, the CTN-KA adduct did not inhibit aflatoxin production by A. parasiticus. These results indicate that CTN’s toxicity was alleviated with KA by converting CTN to the CTN-KA adduct.

Composition-Based Risk Estimation of Mycotoxins in Dry Dog Foods

MDPI

Abstract

The risk of mycotoxins co-occurrence in extrusion-produced dry foods increases due to their composition based on various grains and vegetables. This study aimed to validate a risk estimation for the association between ingredients and the ELISA-detected levels of DON, FUM, ZEA, AFs, T2, and OTA in 34 dry dog food products. The main ingredients were corn, beet, and oil of different origins (of equal frequency, 79.41%), rice (67.6%), and wheat (50%). DON and FUM had the strongest positive correlation (0.635, = 0.001). The presence of corn in the sample composition increased the median DON and ZEA levels, respectively, by 99.45 μg/kg and 65.64 μg/kg, p = 0.011. In addition to DON and ZEA levels, integral corn presence increased the FUM median levels by 886.61 μg/kg, = 0.005. For corn gluten flour-containing samples, DON, FUM, and ZEA median differences still existed, and OTA levels also differed by 1.99 μg/kg, < 0.001. Corn gluten flour presence was strongly associated with DON levels >403.06 μg/kg (OR = 38.4, RR = 9.90, = 0.002), FUM levels >1097.56 μg/kg (OR = 5.56, RR = 1.45, = 0.048), ZEA levels >136.88 μg/kg (OR = 23.00, RR = 3.09, = 0.002), and OTA levels >3.93 μg/kg (OR = 24.00, RR = 3.09, = 0.002). Our results suggest that some ingredients or combinations should be avoided due to their risk of increasing mycotoxin levels.

USA – FDA Warning Letter – Bainbridge Beverage West, LLC- Microbial Risk

FDA

The U.S Food and Drug Administration (FDA) inspected your juice manufacturing facility, located at 2335 Del Monte Street, West Sacramento, CA 95691 on June 9, 10, 22, 24, and 29, 2022. We found that you have serious violations of the FDA’s juice Hazard Analysis and Critical Control Point (HACCP) regulation, Title 21, Code of Federal Regulations, Part 120 (21 CFR Part 120). In accordance with 21 CFR 120.9, failure of a processor to have and implement a HACCP plan that complies with the requirements of 21 CFR Part 120 renders the juice products adulterated within the meaning of Section 402(a)(4) of the Federal Food, Drug and Cosmetic Act (the Act) [21 U.S.C. § 342(a)(4)]. Accordingly, your juice products are adulterated in that they have been prepared, packed, or held under insanitary conditions whereby they may have been contaminated with filth, or whereby they may have been rendered injurious to health. You may find the Act, FDA’s juice HACCP regulations and the Juice HACCP Hazards and Controls Guidance through links in FDA’s home page at www.fda.gov.External Link Disclaimer

To date, the agency has not received a written response from your firm regarding the violations noted on the Form FDA-483, Inspectional Observations, which was issued to your firm at the conclusion of the inspection.