Foodborne pathogens and disease最新文献

Does temperature abuse during storage, distribution, marketing, and consumption of unpasteurized frozen açaí pulp increase microbial hazards? This study investigated the behavior of potentially pathogenic (Escherichia coli, Listeria monocytogenes and Salmonella spp.) and spoilage (mesophilic bacteria, yeasts and molds) microorganisms in two simulated thawing conditions: under refrigeration and at room temperature. The effect of repeated cold chain abuse was observed by thawing and refreezing (-20°C) açaí pulp four times over a period of 90 days. Freezing resulted in inhibition of all microorganisms except for mesophilic aerobic bacteria in one single sample. After thawing at 5°C, the kinetic parameters obtained by the Weibull model indicated that mesophilic aerobic bacteria, yeasts and molds and L. monocytogenes showed a longer inactivation time with δ values reaching 35, 126, and 46 days, respectively. The shortest inactivation time for a reduction of 4 log CFU.g^-1 was for E. coli. The concentration of Salmonella spp. and L. monocytogenes in control samples was higher (p < 0.01) than in samples exposed to abusive conditions after 90 days of storage. The results indicate that the abusive thawing conditions studied do not increase the potential hazards of pathogens.

The development of novel antibacterial agents from plant sources is emerging as a successful strategy to combat antibiotic resistance in pathogens. In this study, we systemically investigated the antibacterial activity and underlying mechanisms of baicalin against methicillin-resistant Staphylococcus aureus (MRSA) and Stenotrophomonas maltophilia. Our results showed that baicalin effectively restrained bacterial proliferation, compromised the integrity of cellular membranes, increased membrane permeability, and triggered oxidative stress within bacteria. Transcriptome profiling revealed that baicalin disrupted numerous biological pathways related to antibiotic resistance, biofilm formation, cellular membrane permeability, bacterial virulence, and so on. Furthermore, baicalin demonstrated a synergistic antibacterial effect when combined with ampicillin against both MRSA and S. maltophilia. In conclusion, baicalin proves to be a potent antibacterial agent with significant potential for addressing the challenge of antibiotic resistance in pathogens.

This study examined data from the Centers for Disease Control and Prevention's National Outbreak Reporting System between 2001 and 2021 for confirmed outbreaks of foodborne illness due to Ciguatoxin in the United States. Previous research into Ciguatoxin illness in the United States has focused on specific states or territories-namely Hawaii, Florida, Puerto Rico, and the Virgin Islands-meaning the national distribution of outbreaks remains unclear. In addition, while specific categories of seafood (e.g., reef fish) are known to carry elevated risk of illness due to Ciguatoxin poisoning, it remains unclear the extent to which specific seafood items are associated with the odds of being hospitalized in an outbreak. This study calculated descriptive statistics for the distribution of outbreaks by state, season, site of exposure, and implicated seafood item. Then, binomial regression was used to assess the relationship between the implicated seafood item in an outbreak and hospitalization. Results provided evidence that knowing the implicated seafood item in an outbreak is associated with the odds of hospitalization (χ²₅ = 33.023, p < 0.0001). Even when a seafood item was found to be associated with elevated odds of hospitalization, not all cases involved hospitalization. This finding aligns with Ciguatoxin poisoning case reports, noting that key epidemiological factors include not just the seafood item consumed but also the quantity and the part consumed (e.g., the head). In conclusion, public health officials should consider Ciguatoxin poisoning outbreaks as multidimensional and utilize information about the seafood consumed as well as the quantity and parts of the seafood consumed.

Contaminated water sources can result in outbreaks of parasitic infections such as Blastocystis sp. in communities, creating a substantial strain on healthcare systems and affecting the general health of the population. To ascertain the prevalence and subtype distribution of Blastocystis sp. in water sources globally, a systematic review and meta-analysis of published papers up to May 19, 2024 were carried out. A thorough search of multiple electronic databases (PubMed, Scopus, Google Scholar, and Web of Science) identified 24 studies/28 datasets meeting the inclusion criteria, encompassing 2,451 water samples from 15 countries worldwide. Water samples comprised wastewater (six datasets, 285 samples), tap/drinking water (10 datasets, 253 samples), surface water (eight datasets, 1013 samples), and uncategorized water (four datasets, 900 samples). Total estimates and 95% confidence intervals (CIs) were computed using a random-effects model. This review found that 18.8% (95% CI: 12.8-26.9%) of examined water samples contained Blastocystis sp. Wastewater showed the highest Blastocystis sp. infection rate at 35.5% (95% CI: 13.5-66.1%), followed by tap/drinking water at 19.1% (95% CI: 9.5-34.5%), surface water at 17.6% (95% CI: 7.2-36.8%), and uncategorized water at 9.9% (95% CI: 4.1-21.8%). Sensitivity analysis assessed weighted prevalence variations following the exclusion of individual studies. Subgroup analysis of Blastocystis sp. prevalence was performed based on publication years, countries, continents, WHO regions, sample sizes, and diagnostic methods. Water samples can be the source of infection for nine Blastocystis sp. subtypes (STs) (ST1-ST4, ST6, ST8, ST10, ST21, and ST24), with seven STs (ST1-ST4, ST6, ST8, and ST10) capable of infecting humans. It is important to take preventative and control measures, improve the cleanliness and quality of water sources, and promote public health awareness due to the presence of different parasites such as Blastocystis sp. in water sources.

The emergence of Motile Aeromonas Septicemia (MAS) caused by Aeromonas veronii in sturgeon farming has become a significant concern due to its high mortality impact on the aquaculture industry. The threat posed by MAS highlights the urgent need for effective control measures to combat bacterial infections in sturgeon populations. Tea polyphenol (TP) has demonstrated promising antibacterial properties against livestock and poultry bacterial infections. However, its antibacterial efficacy and mechanism in bacterial diseases of aquatic animals remain largely unexplored. This study aimed to investigate the in vitro antibacterial effect and mechanism of TP on fish-borne drug-resistant A. veronii TH0426 by assessing the impact of TP on TH0426 cell growth, antibiofilm activity, morphology, as well as measuring electrical conductivity, DNA extravasation, lactate dehydrogenase (LDH) activity, protein, and DNA contents. Results demonstrated that the minimum inhibitory concentration and the minimum bactericidal concentration of TP on TH0426 were 1024 and 2048 μg/mL, respectively. After a 4 h treatment, the growth of TH0426 was completely inhibited at the concentration of 1024 and 2048 μg/mL of TP. Meanwhile, TP exhibited a significant antibiofilm activity. Both scanning electron microscope and transmission electron microscope analyses revealed disrupted cell membrane structure, irregular cell morphology, and loss of intracellular contents following TP treatment. Moreover, increased cell membrane permeability induced by TP led to intracellular ion and DNA leakage, resulting in elevated electrical conductivity and DNA extravasation. Furthermore, TP decreased LDH activity, protein concentration and content, DNA fluorescence intensity, and density in a time-dependent manner, indicating inhibition of protein metabolism and DNA synthesis. In conclusion, TP exhibits potent antibacterial properties by inhibiting biofilm formation, disrupting cell membrane integrity, and interfering with protein metabolism and DNA synthesis in drug-resistant A. veronii TH0426 in vitro.

The plasmid-mediated tet(X4) gene has exhibited a high-level resistance to tigecycline (TGC), which has raised concerns globally regarding antibiotic resistance. Although the widespread tet(X4) has been found widely in Escherichia coli, it is scarcely found in other Enterobacteriaceae. This study aimed to characterize a ST469 Salmonella enterica serovar Rissen (S. Rissen) isolate harboring tet(X4) from pork, which was identified and characterized via antimicrobial susceptibility testing, conjugation assays, plasmid curing testing, whole-genome sequencing, and bioinformatic analysis. Ten ST469 S. Rissen isolates of 223 Salmonella spp. isolates were isolated from food samples in China during 2021-2023. One of 10 S. Rissen isolates, SM2301, carrying tet(X4) conferred high-level resistance to TGC (minimum inhibitory concentration > 8 µg/mL). The tet(X4) could be conjugated into different recipients, including E. coli, S. enteritidis, and K. pneumoniae isolates. Plasmid curing confirmed that tet(X4) was plasmid-mediated. Genetic analysis revealed that the tet(X4) in the SM2301 isolate was located in the IncFIA(HI1)-IncHI1A-IncHI1B(R27) hybrid plasmid, and the structure of tet(X4) was abh-tet(X4)-ISCR2. To the best of our knowledge, this is the first report of a tet(X4)-positive food-derived S. Rissen isolate. The extending bacterial species of tet(X4)-bearing plasmids suggested the increasing transmission risk of the mobile TGC resistance gene tet(X4) beyond E. coli. This study highlights the emerging and evolution risk of novel resistance genes across various bacterial species. Therefore, further surveillance is warranted to monitor the prevalence of tet(X4) in Salmonella spp. and other bacterial species.

Foodborne disease burden estimates inform public health priorities and can help the public understand disease impact. This article provides new estimates of the cost of U.S. foodborne illness. Our research updated disease modeling underlying these cost estimates with a focus on enhancing chronic sequelae modeling and enhancing uncertainty modeling. Our cost estimates were based on U.S. Centers for Disease Control and Prevention estimates of the numbers of foodborne illnesses, hospitalizations, and deaths caused by 31 known foodborne pathogens and unspecified foodborne agents. We augmented these estimates of illnesses, hospitalizations, and deaths with more detailed modeling of health outcomes, including chronic sequelae. For health outcomes, we relied on U.S. data and research where possible, supplemented by the use of non-U.S. research where necessary and scientifically appropriate. Cost estimates were developed from large insurance or hospital charge databases, public data sources, and existing literature and were adjusted to 2023 dollars. We estimated the cost of foodborne illness in the United States circa 2023 to be $75 billion. Deaths accounted for 56% and chronic outcomes for 31% of the mean cost. The costliest pathogen was nontyphoidal Salmonella at $17.1 billion followed by Campylobacter at $11.3 billion. Toxoplasma ($5.7 billion) and Listeria ($4 billion) followed due primarily to deaths and chronic outcomes from pregnancy-associated cases. Per-case cost ranged from $196 for Bacillus cereus to $4.6 million for Vibrio vulnificus. Unspecified agents accounted for 38% of the total cost of foodborne illness, but these illnesses were generally mild (per-case cost $781). These cost estimates can help inform food safety priorities. Our pathogen-specific per-case cost estimates can also help inform benefit-cost analysis required for new federal food safety regulations.

Hydatid cyst is the metacestode stage of Echinococcus granulosus that occurs in herbivores and humans as intermediate hosts by consuming parasite eggs through forage and vegetables. Carnivores, as definitive hosts, become infected by consuming infected vesicles of herbivores. The most effective treatment for a hydatid cyst is surgical operation. Inactivating E. granulosus protoscoleces through heating, cooling, or chemicals such as sodium chloride can be considered an effective method for controlling hydatidosis in both humans and animals. The main objective of this study was to evaluate the effect of different temperatures and salinity conditions on the survival of Echinococcus granulosus protoscoleces. For this purpose, 50 g of infected liver (in triplicate) was separately treated with different temperatures (+10°C, +50°C, +60°C, +72°C, and -20°C) and concentrations of sodium chloride (5%, 10%, 15%, and 20%) for 3, 6, 12, 24, 48, and 72 h. Additionally, 50 g of infected liver was stored separately in the refrigerator (+4°C) as a control group. The survival rate of the protoscoleces was evaluated by staining with 1% eosin under a light microscope. The results showed that the protoscoleces were significantly affected, with 100% mortality at -20°C after 0.5 h, and complete death at +72°C, +60°C, +50°C, and +10°C after 1, 1.5, 3, and 24 h, respectively (p < 0.005). Similarly, the protoscoleces in the liver mass survived at 5% NaCl after 3 h but died at 10% after 24 h, at 15% after 12 h, and at 20% after 6 h. It is concluded that exposing the liver infected with protoscoleces hydatid cyst to a temperature of -20°C and a sodium chloride concentration of 10% for 24 h is suitable for inactivating the protoscoleces.

Despite heavy contamination of the Bogotá River with domestic and industrial waste, it remains vital for various purposes, including agricultural use at La Ramada Irrigation District. There are important concerns regarding pathogen concentrations in irrigation water at La Ramada, including the presence of antibiotic-resistant Salmonella spp. This study aimed to estimate the risk of Salmonella-related illness from consuming lettuce irrigated with Bogotá River water at La Ramada. We collected lettuce samples from 4 different sites, all irrigated with water from La Ramada. The methodology involved a process to detach Salmonella spp. from lettuce leaves, quantification through plate counts on SS agar, and establishment of antibiotic-resistant bacteria concentrations through growth on media supplemented with ampicillin or ciprofloxacin. The results showed concentrations of Salmonella spp. of 10^3.59,10^2.66, and 10^4.56 CFU/g lettuce at sites 1, 2, and 3, respectively, and ampicillin-resistant Salmonella spp. of 10^1.93, 10^1.31, and 10^2.07 CFU/g lettuce at sites 1, 2, and 3, respectively. No colonies were obtained from lettuce samples collected from site 4. Notably, we detected no isolates resistant to ciprofloxacin at any of the sites. Salmonella spp. concentrations varied greatly among sampling sites. Salmonella spp. concentrations were used to predict the daily probability of illness, with a probability of 0.59 (0.33 to 0.78, CI 95%) for Salmonella spp. and 0.3 (0.03 to 0.53, CI 95%) for ampicillin-resistant Salmonella spp.

To investigate the epidemiology of Shiga toxin-producing Escherichia coli (STEC) in dairy cattle, 975 samples (185 feces, 34 silage, 36 cattle drinking water, 360 raw milk, and 360 teat skin swabs) were collected from two dairy farms in Baoji and Yangling, Shaanxi Province, China, and were screened for STEC. Whole-genome sequencing was used to analyze the genomic characteristics and potential transmission of STEC isolates. A total of 32 samples were contaminated with STEC, including 4.0% (19/479) in Farm A and 2.6% (13/496) in Farm B. Compared with adult cows (4.5%), nonadult cows had a higher rate (21.3%) of STEC colonization. A total of 14 serotypes and 11 multilocus sequence typing were identified in 32 STEC isolates, among which O55:H12 (25.0%) and ST101 (31.3%) were the most predominant, respectively. Six stx subtypes/combinations were identified, including stx1a (53.1%), stx2g (15.6%), stx2d, stx2a+stx2d, stx1a+stx2a (6.3%, for each), and stx2a (3.1%). Of 32 STEC isolates, 159 virulence genes and 27 antibiotic resistance genes were detected. Overall, STEC isolates showed low levels of resistance to the 16 antibiotics tested (0-40.6%), with most common resistance to ampicillin (40.6%). The phylogenetic analysis confirmed that STEC in the gut of cattle can be transmitted through feces. The results of this study help to improve our understanding of the epidemiological aspects of STEC in dairy cattle and provide early warning and control of the prevalence and spread of the bacterium.