Prevalence and antimicrobial resistance of major foodborne pathogens isolated from pangas and tilapia fish sold in retail markets of Dhaka city, Bangladesh.

Fish sold at retail markets are often contaminated with harmful bacterial pathogens, posing significant health risks. Despite the growing aquaculture industry in Bangladesh to meet high demand, little attention has been paid to ensuring the safety of fish. The objective of this study was to evaluate the microbiological quality of tilapia and pangas fish sold in retail markets across Dhaka city, Bangladesh. Specifically, the study aimed to compare the quality of fish from traditional wet markets and modern supermarkets, as well as fish samples collected during morning and evening hours. A total of 500 raw cut-fish samples (250 tilapia and 250 pangas) were collected at the point of sale from 32 wet markets and 25 supermarkets. All samples were tested for Escherichia coli, extended-spectrum ß-lactamase-producing E. coli (ESBL-Ec), along with the foodborne pathogens Salmonella, Shigella, Vibrio, and Cryptosporidium spp. Bacterial isolates were characterized using antibiotic susceptibility tests (AST) and the presence of common virulence and antibiotic-resistant genes. Fish samples from retail markets had higher prevalence of tested bacteria including E. coli (92 %), V. cholerae (62 %), ESBL-Ec (48 %), and Salmonella spp. (24 %). There was a significant difference in the prevalence of E. coli (97 % vs. 71 %), ESBL-Ec (58 % vs. 8 %) and Salmonella spp. (28 % vs. 8 %) on the wet market samples compared to supermarket samples (p < 0.005). The mean concentration of E. coli on fish from the wet market was 3.0 ± 0.9 log10 CFU/g, while that from supermarkets was 1.6 ± 0.9 log10 CFU/g. The mean concentration of ESBL-Ec in fish from wet markets and supermarkets were 2.3 ± 0.8 log10 CFU/g and 1.6 ± 0.5 log10 CFU/g, respectively. AST revealed that 46 % of E. coli isolates were multi-drug resistant (MDR), while 4 %, 2 % and 5 % of E. coli, Salmonella spp. and Vibrio spp. isolates, respectively, were resistant to carbapenems. At least 3 % of total E. coli isolates were found to be diarrheagenic, while 40 % of Salmonella isolates harbored pathogenic genes (stn, bcfC, ssaQ, avrA and sodC1), and none of the V. cholerae isolates harbored ctxA and tcpA. Our research shows that raw-cut fish samples from retail markets are contaminated with pathogenic and antibiotic-resistant bacteria, which could be a significant food safety concern. Public health interventions should be implemented to improve food safety and hygiene practices in the retail fish markets.

The COMPARE Database: A Public Resource for Allergen Identification, Adapted for Continuous Improvement.

Motivation: The availability of databases identifying allergenic proteins via a transparent and consensus-based scientific approach is of prime importance to support the safety review of genetically-modified foods and feeds, and public safety in general. Over recent years, screening for potential new allergens sequences has become more complex due to the exponential increase of genomic sequence information. To address these challenges, an international collaborative scientific group coordinated by the Health and Environmental Sciences Institute (HESI), was tasked to develop a contemporary, adaptable, high-throughput process to build the COMprehensive Protein Allergen REsource (COMPARE) database, a publicly accessible allergen sequence data resource along with bioinformatics analytical tools following guidelines of FAO/WHO and CODEX Alimentarius Commission. Results: The COMPARE process is novel in that it involves the identification of candidate sequences via automated keyword-based sorting algorithm and manual curation of the annotated sequence entries retrieved from public protein sequence databases on a yearly basis; its process is meant for continuous improvement, with updates being transparently documented with each version; as a complementary approach, a yearly key-word based search of literature databases is added to identify new allergen sequences that were not (yet) submitted to protein databases; in addition, comments from the independent peer-review panel are posted on the website to increase transparency of decision making; finally, sequence comparison capabilities associated with the COMPARE database was developed to evaluate the potential allergenicity of proteins, based on internationally recognized guidelines, FAO/WHO and CODEX Alimentarius Commission.

Pre-harvest management is a critical practice for minimizing aflatoxin contamination of maize.

Maize, the main dietary staple in Kenya, is one of the crops most susceptible to contamination by aflatoxin. To understand sources of aflatoxin contamination for home grown maize, we collected 789 maize samples from smallholder farmers' fields in Eastern and South Western, two regions in Kenya representing high and low aflatoxin risk areas, respectively, and determined aflatoxin B1 (AFB1) using ELISA with specific polyclonal antibodies. AFB1 was detected in 274 of the 416 samples from Eastern Kenya at levels between 0.01 and 9091.8 µg kg-1 (mean 67.8 µg kg-1). In South Western, AFB1 was detected in 233 of the 373 samples at levels between 0.98 and 722.2 µg kg-1 (mean 22.3 µg kg-1). Of the samples containing AFB1, 153 (55.8%) from Eastern and 102 (43.8%) from South Western exceeded the maximum allowable limit of AFB1 (5 µg kg-1) in maize for human consumption in Kenya. The probable daily intake (PDI) of AFB1 in Eastern Kenya ranged from 0.07 to 60612 ng kg-1 bw day-1 (mean 451.8 ng kg-1 bw day-1), while for South Western, PDI ranged from 6.53 to 4814.7 ng kg-1 bw day-1 (mean 148.4 ng kg-1 bw day-1). The average PDI for both regions exceeded the estimated provisional maximum tolerable daily intake of AFB1, which is a health concern for the population in these regions. These results revealed significant levels of preharvest aflatoxin contamination of maize in both regions. Prevention of preharvest infection of maize by toxigenic A. flavus strains should be a critical focal point to prevent aflatoxin contamination and exposure.

Quantitative assessment of human and pet exposure to Salmonella associated with dry pet foods.

Recent Salmonella outbreaks associated with dry pet foods and treats highlight the importance of these foods as previously overlooked exposure vehicles for both pets and humans. In the last decade efforts have been made to raise the safety of this class of products, for instance by upgrading production equipment, cleaning protocols, and finished product testing. However, no comprehensive or quantitative risk profile is available for pet foods, thus limiting the ability to establish safety standards and assess the effectiveness of current and proposed Salmonella control measures. This study sought to develop an ingredients-to-consumer quantitative microbial exposure assessment model to: 1) estimate pet and human exposure to Salmonella via dry pet food, and 2) assess the impact of industry and household-level mitigation strategies on exposure. Data on prevalence and concentration of Salmonella in pet food ingredients, production process parameters, bacterial ecology, and contact transfer in the household were obtained through literature review, industry data, and targeted research. A probabilistic Monte Carlo modeling framework was developed to simulate the production process and basic household exposure routes. Under the range of assumptions adopted in this model, human exposure due to handling pet food is null to minimal if contamination occurs exclusively before extrusion. Exposure increases considerably if recontamination occurs post-extrusion during coating with fat, although mean ingested doses remain modest even at high fat contamination levels, due to the low percent of fat in the finished product. Exposure is highly variable, with the distribution of doses ingested by adult pet owners spanning 3Log CFU per exposure event. Child exposure due to ingestion of 1g of pet food leads to significantly higher doses than adult doses associated with handling the food. Recontamination after extrusion and coating, e.g., via dust or equipment surfaces, may also lead to exposure due to the absence of pathogen reduction steps after extrusion or at consumer households. Exposure is potentially highest when Salmonella is transferred to human food that is left at growth-promoting conditions. This model can be applied to evaluate the impact of alternative Salmonella control measures during production, risk communication to consumers, and regulatory standards.

Transmission of Bacterial Zoonotic Pathogens between Pets and Humans: The Role of Pet Food.

Recent Salmonella outbreaks associated with dry pet food and treats raised the level of concern for these products as vehicle of pathogen exposure for both pets and their owners. The need to characterize the microbiological and risk profiles of this class of products is currently not supported by sufficient specific data. This systematic review summarizes existing data on the main variables needed to support an ingredients-to-consumer quantitative risk model to (1) describe the microbial ecology of bacterial pathogens in the dry pet food production chain, (2) estimate pet exposure to pathogens through dry food consumption, and (3) assess human exposure and illness incidence due to contact with pet food and pets in the household. Risk models populated with the data here summarized will provide a tool to quantitatively address the emerging public health concerns associated with pet food and the effectiveness of mitigation measures. Results of such models can provide a basis for improvements in production processes, risk communication to consumers, and regulatory action.

A one health framework for estimating the economic costs of zoonotic diseases on society.

This article presents an integrated epidemiological and economic framework for assessing zoonoses using a "one health" concept. The framework allows for an understanding of the cross-sector economic impact of zoonoses using modified risk analysis and detailing a range of analytical tools. The goal of the framework is to link the analysis outputs of animal and human disease transmission models, economic impact models and evaluation of risk management options to gain improved understanding of factors affecting the adoption of risk management strategies so that investment planning includes the most promising interventions (or sets of interventions) in an integrated fashion. A more complete understanding of the costs of the disease and the costs and benefits of control measures would promote broader implementation of the most efficient and effective control measures, contributing to improved animal and human health, better livelihood outcomes for the poor and macroeconomic growth.