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Scientific Reports Aug 2023Listeria outbreaks and food recalls is on the raise globally. Milk particularly is highly susceptible to Listeria as its production and storage adequately support...
Listeria outbreaks and food recalls is on the raise globally. Milk particularly is highly susceptible to Listeria as its production and storage adequately support Listeria growth. The extent of milk contamination with Listeria monocytogenes (Lm) and preventative actions to halt milk associated outbreaks in Africa are unknown. Hence, this study aimed at assessing the national and subregional prevalence of Lm in milk in Africa and identify impacting factors via generalized logistic mixed-effects (GLMEs) and meta-regression modelling. Lm-milk-specific data acquired from primary studies according to standard protocol were fitted using a GLMEs. The GLMEs was subjected to leave-one-study-out-cross-validation (LOSOCV). Factors impacting Lm prevalence in milk were assayed via a 1000-permutation-assisted meta-regression-modelling. The pooled prevalence of Lm in milk in Africa was 4.35% [2.73-6.86] with a prediction interval (PI) of 0.14-59.86% and LOSOCV value of 2.43% [1.62-3.62; PI: 0.32-16.11%]. Western Africa had the highest prevalence [20.13%, 4.13-59.59], then Southern Africa [5.85%, 0.12-75.72], Northern Africa [4.67%, 2.82-7.64], Eastern Africa [1.91%, 0.64-5.55], and there was no record from Central Africa. In term of country, Lm prevalence in milk significantly (p < 0.01) varied from 0.00 to 90.00%. Whereas the Lm prevalence was negligibly different (p = 0.77) by milk type, raw-milk had the highest prevalence [5.26%], followed by fermented-milk [4.76%], boiled-milk [2.90%], pasteurized-milk [1.64%], and powdered-milk [1.58%]. DNA extraction approach did not significantly (p = 0.07) affect Lm prevalence (Boiling [7.82%] versus Kit [7.24%]) as well as Lm detection method (p = 0.10; (ACP [3.64%] vs. CP [8.92%] vs. CS [2.27%] vs. CSP [6.82%]). Though a bivariate/multivariate combination of all tested variables in meta-regression explained 19.68-68.75% (R) variance in Lm prevalence in milk, N, nation, and subregion singly/robustly accounted for 17.61% (F = 7.5994; p = 0.005), 63.89% (F = 4.2028; p = 0.001), and 16.54% (F = 3.4743; p = 0.026), respectively. In conclusion, it is recommended that adequate sample size should be prioritized in monitoring Lm in milk to prevent spuriously high or low prevalence to ensure robust, plausible, and credible estimate. Also, national efforts/interests and commitments to Lm monitoring should be awaken.
Topics: Animals; Listeria monocytogenes; Milk; Food Contamination; Prevalence; Listeria; Africa, Southern; Food Microbiology
PubMed: 37542148
DOI: 10.1038/s41598-023-39955-0 -
Journal of Veterinary Research Sep 2023is an important foodborne pathogen responsible for human listeriosis, which is a disease with high hospitalisation and mortality rates. The bacteria are usually...
INTRODUCTION
is an important foodborne pathogen responsible for human listeriosis, which is a disease with high hospitalisation and mortality rates. The bacteria are usually susceptible to most antibacterial substances, but resistance to some of them has been recently observed. The present study introduces the evidence on the emergence of antibiotic resistance among strains isolated from food and food-production environments in Poland.
MATERIAL AND METHODS
A total of 283 isolates classified into serogroups IIa and IVb which had been recovered from food and food production environments were tested with 17 antimicrobials. These included those that are recommended for treatment of severe listeriosis cases in humans. A multiplex PCR was used to identify serogroups, and a microbroth dilution method was applied for the determination of antibiotic resistance among the isolates tested.
RESULTS
Only 34 (12.0%) strains were susceptible to all the antimicrobials used in the study. The remaining 249 (88.0%) strains displayed different instances of resistance to the antimicrobials tested, from insusceptibility to one (112 strains; 39.6%) to resistance to four antibacterial substances (6 strains; 2.1%). Among them, there were 38 strains (13.4%) with multiresistance patterns.
CONCLUSION
Polish food and its processing environments may be a potential source of antimicrobial-resistant , which may pose a potential health risk to consumers in the country.
PubMed: 37786847
DOI: 10.2478/jvetres-2023-0050 -
Foodborne Pathogens and Disease May 2024Gut microbiota (GM) has been proven to resist pathogenic infection through nutritional competition, colonization resistance and promotion of the host immune response....
Gut microbiota (GM) has been proven to resist pathogenic infection through nutritional competition, colonization resistance and promotion of the host immune response. However, in clinical practice, GM is mainly used in intestinal diseases, such as infection, and there are few reports on its application in the treatment of pathogenic bacterial infections. In this study, GM from healthy mice was transplanted into mice infected with using fecal microbiota transplantation (FMT) and the effects were observed. We found that GM from healthy mice could reduce the mortality of infected mice and decrease the counts of in their liver and spleen. In addition, FMT inhibited the expression of inflammatory factors in the liver and spleen of infected mice. cell experiments revealed that GM can reduce the count of invading Caco-2 cells and inhibit the -caused apoptosis. These results indicate that GM can be used to protect mice infected with by eliminating the amount of in the host and inhibiting the overexpression of inflammatory factors. Hence, this method can potentially replace antibiotics in the treatment of infection.
Topics: Animals; Listeriosis; Gastrointestinal Microbiome; Listeria monocytogenes; Apoptosis; Mice; Fecal Microbiota Transplantation; Cytokines; Humans; Caco-2 Cells; Liver; Spleen; Female
PubMed: 38237167
DOI: 10.1089/fpd.2023.0121 -
International Journal of Food... Aug 2024Despite the wide variety of native and exotic fruits in Brazil, there is limited understanding of their ability to support pathogens during storage. This study aimed to...
Despite the wide variety of native and exotic fruits in Brazil, there is limited understanding of their ability to support pathogens during storage. This study aimed to evaluate the behavior of Salmonella enterica and Listeria monocytogenes inoculated into the pulp of eight fruits native and exotic to Brazil: Jenipapo (Genipa americana L.), Umbu (Spondias tuberosa Arruda), Maná (Solanum sessiliflorum), Cajá-manga (Spondias dulcis), Physalis (Physalis angulata L.), Feijoa (Acca sellowiana), Cupuaçu (Theobroma grandiflorum) (average pH < 3.3) and in a low acidy fruit: Abiu (Pouteria caimito) (pH 6.11). The pathogens were inoculated into the different fruits and stored at 10, 20, 30 and 37 °C for up to 12 h and 6 days, respectively. Among the fruits evaluated, Abiu was the only one that allowed Salmonella growth, showing higher δ-values at 20 and 30 °C (5.6 log CFU/g for both temperatures). For Physalis and Feijoa, there was a small reduction in the pathogen concentration (<1 log-cycle), mainly at 10 and 20 °C, indicating its ability to remain in the matrices. For the other fruits, notable negative δ-values were obtained, indicating a tendency towards microbial inactivation. The survival potential was significantly affected by temperature in Abiu, Maná, Cupuaçu, and Cajá-manga (p < 0.05). The same phenomena regarding δ-value were observed for L. monocytogenes population, with the greatest survival potential observed at 20 °C in Abiu (3.3 log CFU/g). Regarding the exponential growth rates in Abiu, the highest values were observed at 30 and 37 °C, both for Salmonella (4.6 and 4.9 log (CFU/g)/day, respectively) and for L. monocytogenes (2.8 and 2.7 log (CFU/g)/day, respectively), with no significant difference between both temperatures. Regarding microbial inactivation, L. monocytogenes showed greater resistance than Salmonella in practically all matrices. Jenipapo and Umbu were the pulps that, in general, had the greatest effect on reducing the population of pathogens. Furthermore, the increase in storage temperature seems to favor the increase on inactivation rates. In conclusion, Salmonella and L. monocytogenes can grow only in Abiu pulp, although they can survive in some acidic tropical fruits kept at refrigeration and abusive temperatures.
Topics: Salmonella enterica; Listeria monocytogenes; Fruit; Brazil; Food Microbiology; Temperature; Colony Count, Microbial; Food Contamination; Food Storage
PubMed: 38851046
DOI: 10.1016/j.ijfoodmicro.2024.110783 -
Cells Dec 2023Vertically transmitted infections are a significant cause of fetal morbidity and mortality during pregnancy and pose substantial risks to fetal development. These... (Review)
Review
Vertically transmitted infections are a significant cause of fetal morbidity and mortality during pregnancy and pose substantial risks to fetal development. These infections are primarily transmitted to the fetus through two routes: (1) direct invasion and crossing the placenta which separates maternal and fetal circulation, or (2) ascending the maternal genitourinary tact and entering the uterus. Only two bacterial species are commonly found to cross the placenta and infect the fetus: and subsp. . is a Gram-positive, foodborne pathogen found in soil that acutely infects a wide variety of mammalian species. is a sexually transmitted spirochete that causes a chronic infection exclusively in humans. We briefly review the pathogenesis of these two very distinct bacteria that have managed to overcome the placental barrier and the role placental immunity plays in resisting infection. Both organisms share characteristics which contribute to their transplacental transmission. These include the ability to disseminate broadly within the host, evade immune phagocytosis, and the need for a strong T cell response for their elimination.
Topics: Pregnancy; Humans; Animals; Female; Treponema pallidum; Placenta; Listeria monocytogenes; Treponema; Mammals
PubMed: 38201292
DOI: 10.3390/cells13010088 -
PloS One 2023Listeria monocytogenes is motile at 22°C and non-motile at 37°C. In contrast, expression of L. monocytogenes virulence factors is low at 22°C and up-regulated at...
Listeria monocytogenes is motile at 22°C and non-motile at 37°C. In contrast, expression of L. monocytogenes virulence factors is low at 22°C and up-regulated at 37°C. Here, we studied a character of L. monocytogenes near surface swimming (NSS) motility and its effects on adhesion patterns and invasion into epithelial cells. L. monocytogenes and its saprophytic counterpart L. innocua both grown at 22°C showed similar NSS characteristics including individual velocities, trajectory lengths, residence times, and an asymmetric distribution of velocity directions. Similar NSS patterns correlated with similar adhesion patterns. Motile bacteria, including both pathogenic and saprophytic species, showed a preference for adhering to the periphery of epithelial HEp-2 cells. In contrast, non-motile bacteria were evenly distributed across the cell surface, including areas over the nucleus. However, the uneven distribution of motile bacteria did not enhance the invasion into HEp-2 cells unless virulence factor production was up-regulated by the transient shift of the culture to 37°C. Motile L. monocytogenes grown overnight at 22°C and then shifted to 37°C for 2 h expressed invasion factors at the same level and invaded human cells up to five times more efficiently comparatively with non-motile bacteria grown overnight at 37°C. Taken together, obtained results demonstrated that (i) NSS motility and correspondent peripheral location over the cell surface did not depend on L. monocytogenes virulence traits; (ii) motility improved L. monocytogenes invasion into human HEp-2 cells within a few hours after the transition from the ambient temperature to the human body temperature.
Topics: Humans; Listeria monocytogenes; Physical Phenomena; Cell Membrane; Cell Nucleus; Epithelial Cells; Tissue Adhesions; Virulence Factors
PubMed: 37651463
DOI: 10.1371/journal.pone.0290842 -
Critical Reviews in Food Science and... 2024, a causative agent of listeriosis, is a major foodborne pathogen. Among pathogens, stands out for its unique ecological and physiological characteristics. This... (Review)
Review
, a causative agent of listeriosis, is a major foodborne pathogen. Among pathogens, stands out for its unique ecological and physiological characteristics. This distinct lifestyle of has a significant impact on food safety and public health, mainly through the ability of this pathogen to multiply at refrigeration temperature and to persist in the food processing environment. Due to a combination of these characteristics and emerging trends in consumer preference for ready-to-eat and minimally processed food, there is a need to develop effective and sustainable approaches to control contamination of food products with . Implementation of an efficient and reliable control strategy for must first address the problem of cross-contamination. Besides the preventive control strategies, cross-contamination may be addressed with the introduction of emerging post packaging non-thermal or thermal hurdles that can ensure delivery of a listericidal step in a packed product without interfering with the organoleptic characteristics of a food product. This review aims to present the most relevant findings underlying the distinct lifestyle of and its impact on food safety. We also discuss emerging food decontamination technologies that can be used to better control .
Topics: Humans; Listeria monocytogenes; Food Contamination; Food Microbiology; Listeriosis; Food-Processing Industry
PubMed: 36062812
DOI: 10.1080/10408398.2022.2119205 -
Heliyon Jul 2023Smoked salmon and smoked trout are ready-to-eat and potentially contaminated with the pathogenic bacterium making them high risk for the consumer. This raises questions...
Smoked salmon and smoked trout are ready-to-eat and potentially contaminated with the pathogenic bacterium making them high risk for the consumer. This raises questions about the presence of hypervirulent or persistent strains in the salmon and trout industries. Knowledge of the genetic diversity of circulating strains in these sectors is essential to evaluate the risk associated with this pathogen and improve food safety. We analyzed the genetic structure of 698 strains of isolated from 2006 to 2017 in France, based on their serogroup, lineage and clonal complexes (CCs) determined by Multilocus sequence typing (MLST). Most of the CCs were identified by mapping the strains PFGE profiles and a novel high-throughput real-time PCR method for CC identification. We identified thirteen CCs and one sequence type (ST) with variable distribution in salmon and trout samples (food, environment). The three most prevalent CCs were CC121, CC26 and CC204. Strains from ST191 and CC54 were detected for the first time in these sectors, while less than 0.6% of the isolates belonged to the hyper-virulent CC1, CC6 and CC20. No CC was exclusively associated with the salmon sector. This project allowed us to assess the population diversity of CCs of in the salmon and trout industries.
PubMed: 37483814
DOI: 10.1016/j.heliyon.2023.e18154 -
International Journal of Food... Aug 2023Listeria monocytogenes can adapt, persist, and form biofilms on food premises surfaces, representing a challenge for food safety, since they led to disease transmission,...
Listeria monocytogenes can adapt, persist, and form biofilms on food premises surfaces, representing a challenge for food safety, since they led to disease transmission, food contamination and spoilage during production. Physical interventions (scrubbing and wiping) can help controlling formation, nevertheless when biofilms are formed, they are usually very resistant to current control strategies used in the food industry. Biofilm attachment and formation is influenced by environment characteristics, substrate properties and microbial motility. The purpose of this study was to evaluate the ability of L. monocytogenes to attach and form biofilms on different surfaces (wood, nylon, and polycarbonate) representative of the materials used during produce harvesting and storage. Multi-strain L. monocytogenes biofilms were grown in a CDC Biofilm reactor at 20 ± 2 °C up to 96-h and characterized for: a) attachment strength by enumerating cells after rinsing; b) hydrophobicity and interfacial tension by contact angle measurements; c) biofilm architecture by Laser Scanning Confocal Microscopy. All experiments were done in triplicate. Material, incubation, and solvent significantly affected the hydrophobicity and wetting properties of L. monocytogenes biofilms (P < 0.05). The type of material and incubation time significantly influenced hydrophobicity and wetting properties of L. monocytogenes biofilms (P < 0.05). Highest contact angle and lowest interfacial tension were observed on polycarbonate coupons. The data presented contributes to understanding Listeria biofilms grow on different surfaces commonly used in produce harvesting and storage. The data obtained in this study can be used when evaluating intervention strategies to control this pathogen in food premises.
Topics: United States; Listeria monocytogenes; Food Microbiology; Biofilms; Food Contamination; Centers for Disease Control and Prevention, U.S.; Stainless Steel
PubMed: 37244228
DOI: 10.1016/j.ijfoodmicro.2023.110251 -
Frontiers in Microbiology 2023The contamination of ready to eat foods (RTE) products due to could compromise the products safety becoming a great risk for the consumers. The high presence of in RTE...
The contamination of ready to eat foods (RTE) products due to could compromise the products safety becoming a great risk for the consumers. The high presence of in RTE products has been described worldwide, but few data are available about these products from African countries. The aims of this study were to report the presence of in Zambian RTE products, providing genomic characterization and data on similarity with African circulating strains using whole genome sequencing (WGS). A total of 304 RTE products, produced by different Zambian manufacturers, were purchased at retail, from major supermarkets located in Lusaka, Zambia, comprising 130 dairy and 174 meat products. was detected only in 18 (10.3%) RTE meat products of the 174 samples tested. The MLST analysis grouped the 18 isolates in 7 clonal complexes (CCs): CC1 ( = 5), CC2 ( = 4), CC9 ( = 4), CC5 ( = 2), CC121 ( = 1), CC155 ( = 1), and CC3 ( = 1). According to the cgMLST results, several clusters were detected, in particular belonging to hyper-virulent clones CC1 and CC2. Regarding the virulence factors, a complete Pathogenicity Island 3 (LIPI-3) was present both in the CC1 and CC3, in addition to LIPI-1. Several resistance genes and mobile genetic elements were detected, including Stress Islands, the cassette and _qac transposon, plasmids and intact prophages. Despite being a first preliminary work with a limited number of samples and isolates, this study helped to increase existing knowledge on contaminated RTE products in Zambia, confirming the presence of hyper-virulent CCs, which could play an important role in human diseases, posing a public health concern for consumers.
PubMed: 37711697
DOI: 10.3389/fmicb.2023.1228726