Pathogens In Seafood Research Articles

Seagrass ecosystems as green urban infrastructure to mediate human pathogens in seafood

Seagrass ecosystems as green urban infrastructure to mediate human pathogens in seafood

Rapid and simultaneous detection of Salmonella Sp. and Staphylococcus aureus in seafood by Multiplex PCR (mPCR)

aims: The present study is to investigate the prevalence of Salmonella sp. and Staphylococcus in seafood sample using multiplex polymerase chain reaction (mPCR). background: The rapid detection of food borne pathogen is increasing to ensure safety to consumers as major food borne illness is caused by pathogenic bacteria. Salmonellosis caused by Salmonella sp. is one of the primary concerns in many countries. Staphylococcus aureus is capable of generating toxins which can produce food poisoning in human body. objective: The thermostable nuclease (nuc) gene of Staphylococcus aureus and enterotoxin (stn) gene of Salmonella were used as target genes for mPCR detection. method: Totally, 10 seafood which includes fishes, crab and prawns which are generally available in Indian fish markets were selected for the present study. Samples that carried both the strains Salmonella and Staphylococcus were selected for mPCR by targeting the stn and nuc gene. result: Among 10 seafood samples collected, 7 of them carried Salmonella strain and 5 of them carried Staphylococcus strains. The results showed that 75% of the salmonella strains carried stn gene and 75% of the Staphylococcus strains carried nuc gene. conclusion: This study suggests that mPCR can be used for simultaneous detection by targeting the stn gene and nuc gene of salmonella and Staphylococcus food borne pathogens in seafood. other: Not applicable

Pathogens associated with seafood exports from Southeast Asia to the European Union: Analysis of the Rapid Alert System for Food and Feed (1997–2020)

Over the years, the need for healthy food has increased the demand for seafood in the international market. However, despite the high global demand, seafood is highly perishable and may harbour pathogenic microorganisms that could be transferred to humans during handling, processing, and consumption. Therefore, establishing strict food safety standards and risk communication tools is critical to prevent the infiltration of unsafe seafood into global markets. In the global food supply chain, the European Union (EU) is the largest importer of seafood, while more than 80% of global seafood production is from Asia. Additionally, Southeast Asian countries account for 32% of global seafood production. Therefore, this study aimed to evaluate the microbiological safety of seafood imported from Southeast Asia to the EU by analysing alert notifications in the Rapid Alert System for Food and Feed (RASFF) database. The RASFF is a tool used for reporting and communicating food safety-related risks among the EU Member States and other members of the RASFF network. A total of 301 notifications of pathogens in seafood originating from four Southeast Asian countries (Malaysia, Thailand, Vietnam, and Indonesia) were reported by 19 EU countries, including the United Kingdom (1997-2020). More than 56% of the pathogen notifications involved crustaceans and related products. Fifty-two percent of the notifications involved seafood from Vietnam, while 30% of the notifications from EU member countries were from Italy. Vibrio spp. was the most predominant bacterial pathogen responsible for 50% of the notifications, followed by Salmonella spp. and Clostridium accounting for 38% and 2% of the notifications, respectively. Norovirus was implicated in 10% of the notifications, and this was only in clams from Vietnam. These pathogens pose a risk to consumers’ health, indicating the need to enforce stringent food safety standards in producing countries to ensure the safety of seafood exported to other parts of the world. These actions will ultimately prevent economic loss associated with the rejection, destruction or import restrictions of contaminated seafood originating from Southeast Asia to the EU.

Gold Nanoparticle Paper Immunoassays for Sensing the Presence of Vibrio parahaemolyticus in Oyster Hemolymph.

Seafood contamination with Vibrio bacteria is a problem for aquaculture, especially with oysters, which are often consumed raw. Current methods for diagnosing bacterial pathogens in seafood involve lab-based assays such as polymerase chain reaction or culturing, which are time consuming and must occur in a centralized location. Detection of Vibrio in a point-of-care assay would be a significant tool for food safety control measures. We report here a paper immunoassay that can detect the presence of Vibrio parahaemolyticus (Vp) in buffer and oyster hemolymph. The test uses gold nanoparticles conjugated to polyclonal anti-Vibrio antibodies in a paper-based sandwich immunoassay. A sample is added to the strip and wicked through by capillary action. If Vp is present, it results in a visible color at the test area that can be read out by eyes or a standard mobile phone camera. The assay has a limit of detection of 6.05 × 105 cfu/mL and a cost estimate of $5 per test. Receiver operating characteristic curves with validated environmental samples showed a test sensitivity of 0.96 and a specificity of 1.00. Because the assay is inexpensive and can be used on Vp directly without the requirement for culturing, or sophisticated equipment, it has the potential to be used in fieldable settings.

Prevalence of Antibiotic-Resistant Seafood-Borne Pathogens in Retail Seafood Sold in Malaysia: A Systematic Review and Meta-Analysis.

The objective of this study was to examine the frequency and extent of antibiotic-resistant pathogens in seafood sold in Malaysia, using a systematic review and meta-analysis approach to analyze primary research studies. Four bibliographic databases were systematically searched for primary studies on occurrence. Meta-analysis using a random-effect model was used to understand the prevalence of antibiotic-resistant bacteria in retail seafood sold in Malaysia. A total of 1938 primary studies were initially identified, among which 13 met the inclusion criteria. In the included primary studies, a total of 2281 seafoods were analyzed for the presence of antibiotic-resistant seafood-borne pathogens. It was observed that 51% (1168/2281) of the seafood was contaminated with pathogens. Overall, the prevalence of antibiotic-resistant seafood-borne pathogens in retail seafood was 55.7% (95% CI: 0.46-0.65). Antibiotic-resistant Salmonella species had an overall prevalence of 59.9% (95% CI: 0.32-0.82) in fish, Vibrio species had an overall prevalence of 67.2% (95% CI: 0.22-0.94) in cephalopods, and MRSA had an overall prevalence of 70.9% (95% CI: 0.36-0.92) in mollusks. It could be concluded that there is a high prevalence of antibiotic-resistant seafood-borne pathogens in the retail seafood sold in Malaysia, which could be of public health importance. Therefore, there is a need for proactive steps to be taken by all stakeholders to reduce the widespread transmission of antibiotic-resistant pathogens from seafood to humans.

Bacteriological Assessment of Smoked-Dried White Shrimp (Nematopalaemon hastatus Aurivillius, 1898) Sold in Calabar, Nigeria

Aim: Enumeration of bacterial counts is an important index of assessing the safety and quality of food products. This study aimed to investigate the occurrence of pathogenic bacteria in white shrimp samples obtained from major markets serving consumers in Calabar.
 Study Design: This study was a cross sectional study conducted between April 2017 and April 2018.
 Methodology: One hundred and twenty (120) samples of smoked dried Nematopalaemon hastatus (white shrimp) were analyzed for the presence of bacterial pathogens. Bacterial loads and identification of isolated organisms was determined using standard microbiological methods.
 Results: The results showed that 66.7% of the analyzed shrimps had aerobic bacterial counts exceeding the upper permissible limit (<1.0x106Cfu/g) and 56.7% had unsatisfactory (˃20Cfu/g) Vibrio counts. The study revealed the presence of different bacteria genera namely Klebsiella, Salmonella, Pseudomonas, Serratia, Vibrio, Citrobacter, Proteus, Aeromonas, Streptococcus, Escherichia, Coagulase-negative Staphylococci (CoNS), Enterobacter and Bacillus. Predominant organism was Salmonella spp (26.7%), followed by Vibrio spp (21.7%) while the least isolated organisms were Bacillus spp and Coagulase-Negative Staphylococci (1.7%) each. The occurrence of high counts of pathogens in seafood may cause food poisoning; especially in individuals who consume this seafood raw, or lightly or insufficiently cooked.
 Conclusion: Hence, seafood should be processed and packaged under standard hygienic conditions to reduce the risk of microbial contamination. In addition, public health awareness campaign targeted at consumers and vendors should be optimized with frequent monitoring by regulatory agencies.

Probe-based Loop-Mediated Isothermal Amplification Assay for Multi-target Quantitative Detection of Three Foodborne Pathogens in Seafood

Probe-based Loop-Mediated Isothermal Amplification Assay for Multi-target Quantitative Detection of Three Foodborne Pathogens in Seafood

An ultra-fast, one-step RNA amplification method for the detection of Salmonella in seafood.

Salmonella is one of the most common pathogens associated with food-borne illness resulting from seafood consumption. Herein, an accelerated strand exchange amplification (ASEA) requiring only a pair of primers and one polymerase was first reported for ultra-fast, one-step RNA amplification detection of Salmonella in seafood. The ASEA method could detect Salmonella typhimurium DNA in dilutions as low as 10 copies per reaction and displayed good specificity for Salmonella under the interference of a variety of food-borne pathogens. In particular, ASEA could detect RNA in one step without additional reverse transcription. The detection limit for Salmonella in artificially contaminated oyster was 1 CFU mL-1 following 12 h of enrichment. Moreover, excellent performance of this assay was observed with 99.02% consistency relative to real-time PCR through actual sample detection. Combined with the rapid nucleic acid extraction method, the entire detection process could be completed within 20 min. Therefore, this assay opens up new prospects for the detection of food-borne pathogens in seafood with its rapidity, which would be very beneficial for food safety supervision and pathogen detection of high-throughput samples.

Analysis of Raman Spectra by Using Deep Learning Methods in the Identification of Marine Pathogens.

The need for efficient and accurate identification of pathogens in seafood and the environment has become increasingly urgent, given the current global pandemic. Traditional methods are not only time consuming but also lead to sample wastage. Here, we have proposed two new methods that involve Raman spectroscopy combined with a long short-term memory (LSTM) neural network and compared them with a method using a normal convolutional neural network (CNN). We used eight strains isolated from the marine organism Urechis unicinctus, including four kinds of pathogens. After the models were configured and trained, the LSTM methods that we proposed achieved average isolation-level accuracies exceeding 94%, not only meeting the requirement for identification but also indicating that the proposed methods were faster and more accurate than the normal CNN models. Finally, through a computational approach, we designed a loss function to explore the mechanism reflected by the Raman data, finding the Raman segments that most likely exhibited the characteristics of nucleic acids. These novel experimental results provide insights for developing additional deep learning methods to accurately analyze complex Raman data.

Presence of Foodborne Pathogens in Seafood and Risk Ranking for Pathogens.

This study aims at examining the contamination of coliform bacteria, Escherichia coli, Listeria monocytogenes, Vibrio vulnificus, and Vibrio cholerae, which carry extremely serious risks to the consumer health, in 700 seafood belonging to 4 different (raw sea fish, raw mussels, raw shrimp, and raw squid) categories. The total number of samples was determined as 700. When the obtained results were viewed in total, they were found to be 48.14%, 18.71%, 8.57%, and 3.42% for coliform bacteria, E. coli, L. monocytogenes, and V. vulnificus, respectively. V. cholerae, one of the factors studied, was not found. Conventional microbiological cultivation methods were used in the analysis stage as well as the real-time PCR method. This study aims at making a risk ranking modeling for consumer health based on product category and pathogens by interpreting the results of the analysis with statistical methods. According to the statistical analysis, significantly binary correlations were determined among some parameters that stimulate one another for reproducing. In the light of the obtained results of the study, it has been concluded that the studies of the most detailed examinations of the microbiological risks associated with seafood, forms of microbial pollution and microorganisms that cause deterioration in seafood and threaten consumer health and the path that their epidemiologies follow, are of primary importance to both protecting consumer health and obtaining safe and quality seafood.

Multiplex Recombinase Polymerase Amplification Assay for the Simultaneous Detection of Three Foodborne Pathogens in Seafood.

Foodborne pathogens can cause foodborne illness. In reality, one food sample may carry more than one pathogen. A rapid, sensitive, and multiple target method for bacteria detection is crucial in food safety. For the simultaneous detection of Staphylococcus aureus, Vibrio parahaemolyticus, and Salmonella Enteritidis, multi-objective recombinase polymerase amplification (RPA) combined with a lateral flow dipstick (LFD) was developed in this study. The whole process, including amplification and reading, can be completed in 15 min at 37 °C. The detection limits were 2.6 × 101 CFU/mL for Staphylococcus aureus, 7.6 × 101 CFU/mL for Vibrio parahaemolyticus, and 1.29 × 101 CFU/mL for Salmonella Enteritidis. Moreover, colored signal intensities on test lines were measured by a test strip reader to achieve quantitative detection for Staphylococcus aureus (R2 = 0.9903), Vibrio parahaemolyticus (R2 = 0.9928), and Salmonella Enteritidis (R2 = 0.9945). In addition, the method demonstrated good recoveries (92.00%–107.95%) in the testing of spiked food samples. Therefore, the multiplex LFD-RPA assay is a feasible method for the rapid, sensitive, and quantitative detection of bacterial pathogens in seafood.

Rapid pathogen detection tools in seafood safety

Detection, identification, and monitoring of pathogens in seafood are critical in achieving seafood safety goals. Rapid detection techniques enable outcome of fast and reliable results especially with expansion in the global trade requiring rapid transport over long distances. This review summarizes some of the major techniques in use and recent advances for rapid detection of pathogens in seafood which can be broadly classified into nucleic acid-based, antigen-antibody based, biosensor-based and phage-based methods. Selection of an appropriate pathogen detection method along with a combination of several other state-of-art technologies can as well ensure the effectiveness of pathogen detection and aid in ameliorating seafood safety.

Effects of varying concentrations of sodium chloride and acidic conditions on the behavior of Vibrio parahaemolyticus and Vibrio vulnificus cold-starved in artificial sea water microcosms.

There has been limited information available on the behavior of Vibrio parahaemolyticus and Vibrio vulnificus as a function of higher levels of NaCl in combination with acidic pH. In the present study, bacterial suspensions were transferred into artificial seawater (pH 4-7) microcosms containing 0.75% NaCl and supplemented with 5, 10, and 30% NaCl, respectively. Each of V. parahaemolyticus and V. vulnificus was inoculated in these microcosms and fermented seafood, and then stored at 4°C until the microbial populations reached below the detectable levels on agar plates (thiosulphate-citrate-bile salts-sucrose agar and tryptic soy agar amended with 3% NaCl). Consequently, V. parahaemolyticus ATCC 27969, V. parahaemolyticus ATCC 33844, and V. vulnificus ATCC 33815 rapidly reached the viable-but-nonculturable (VBNC) state with increasing levels (≤30%) of NaCl at 4°C. Within seven days, these pathogens in seafood appeared to enter the VBNC state at 4°C, as shown by the fluorescence microscopic assay.

BACTERIOLOGICAL HAZARDS AND RISKS ASSOCIATED WITH SEAFOOD CONSUMPTION IN BRAZIL

SUMMARY The present study is a review of data available in Brazil on bacterial diseases transmitted through the consumption of seafood and related products. Data are presented regarding outbreaks and cases of disease and laboratory findings associated with pathogens in seafood and related products, and methods for prevention and control are described.

Adaptive Radiation within Marine Anisakid Nematodes: A Zoogeographical Modeling of Cosmopolitan, Zoonotic Parasites

Parasites of the nematode genus Anisakis are associated with aquatic organisms. They can be found in a variety of marine hosts including whales, crustaceans, fish and cephalopods and are known to be the cause of the zoonotic disease anisakiasis, a painful inflammation of the gastro-intestinal tract caused by the accidental consumptions of infectious larvae raw or semi-raw fishery products. Since the demand on fish as dietary protein source and the export rates of seafood products in general is rapidly increasing worldwide, the knowledge about the distribution of potential foodborne human pathogens in seafood is of major significance for human health. Studies have provided evidence that a few Anisakis species can cause clinical symptoms in humans. The aim of our study was to interpolate the species range for every described Anisakis species on the basis of the existing occurrence data. We used sequence data of 373 Anisakis larvae from 30 different hosts worldwide and previously published molecular data (n = 584) from 53 field-specific publications to model the species range of Anisakis spp., using a interpolation method that combines aspects of the alpha hull interpolation algorithm as well as the conditional interpolation approach. The results of our approach strongly indicate the existence of species-specific distribution patterns of Anisakis spp. within different climate zones and oceans that are in principle congruent with those of their respective final hosts. Our results support preceding studies that propose anisakid nematodes as useful biological indicators for their final host distribution and abundance as they closely follow the trophic relationships among their successive hosts. The modeling might although be helpful for predicting the likelihood of infection in order to reduce the risk of anisakiasis cases in a given area.