Risk of Escherichia coli O157:H7 infection linked to the consumption of beef

Escherichia coli O157:H7 is a major food-borne pathogen that has resulted in numerous outbreaks around the world. Widespread distribution of the organism in various ecological niches impedes the control measures. This study aimed to detect and quantify E. coli O157:H7 in beef sold in wet markets and hypermarkets in Malaysia and to determine the risk of E. coli O157:H7 infection linked to consumption of beef. The rfb O157 and flicH7 primers targeted on somatic antigen (O157) and flagellar antigen (H7) respectively of E. coli O157:H7 was used for the MPN-PCR method. A total of 99 beef samples were collected from local wet markets and hypermarkets. The highest E. coli O157:H7 contamination rate was observed in beef samples collected from wet markets (89.50%), whereas the contamination rate in hyper market A and B were compratively low (35.35 and 20% respectively). However, the microbial load was highest in the beef samples from hypermarket A (1100 MPN/g) while E. coli O157:H7 bacterial load in beef samples from hypermarket B and wet market ranged from 3 to 93 MPN/g and 3 to 240 MPN/g, respectively. Using the Quantitative Microbial Risk Assessment (QMRA) approach the risk was estimated incorporating the findings of the prevalence study and predictions based on home storage, cooking and consumption patterns. Three different exposure pathways were investigated to estimate the risk associated with contaminated beef and Monte Carlo simulation was used to determine the level of uncertainty. The developed model predicated that consumption of contaminated beef can be accountable for 1.83E+06 E. coli O157:H7 cases per year in Malaysia. The reliability of the model, data gaps and further research needs, is discussed. Through continuous improvement Quantitative Microbial Risk Assessment provides valuable insight into controlling and prevention strategies

Microwave oven safety: a food safety consumer survey in Malaysia

Microwave oven is an indispensable tool in every household. However, the proper usage of the microwave ovens was neglected and thus, causing food safety concerns, especially microbiological hazard in microwaved heated food. Therefore, a survey was initiated to gauge the consumer’s knowledge of microwave oven safety concerning the food safety of reheated food. A total of 29 survey questions was designed that covered 5 demographic questions and 24 others on the knowledge and practice of microwave oven safety and food safety attitude. The survey was blasted out to 329 respondents via email. Overall, 189 (57.4%) returned respondents demonstrated low level of knowledge of the microwave oven safety, which indicated improper education of the microwave oven despite knowing the norms on the microwave oven usage. In addition, consumers demonstrated low levels of practicing microwave oven safety. The outcome of the survey also showed consumer’s neutral attitude towards food safety. There was no statistically significant association between the variables and demographic. The minimum knowledge of microwave oven and food safety shown by the consumers requires the attention to improve the food safety educational programs by including the knowledge on microwave oven safety for the betterment of the public health

Distribution of bacteriophages in food and environment samples

Foodborne pathogens have become a constant threat to the consumer and food industry. Reduce efficacy of antibiotics with emergence of resistant bacteria has limited the opportunities for controlling pathogenic bacteria in food commodities and treating foodborne infections. Bacteriophages can be a promising alternative for alleviate the risk of transmitting pathogenic bacteria via food commodities. Therefore, this research was conducted to find distribution of bacteriophages in diverse niches in order to identify suitable sources for isolating bacteriophages to use controlling foodborne pathogens. Firstly bacterial strains were screened for lysogenic and selected suitable host bacterial strains were used for isolating and determining bacteriophage titer in fresh raw food and environmental samples. Eighteen different lytic bacteriophages effective against Campylobacter, S. aureus, L. monocytogenes and E. coli were isolated from this study. Bacteriophages titer was determined within range of 102 to 1010 PFU/mL and bacteriophages were most frequently isolated from chicken (60%) samples. The isolated bacteriophages could be potential candidates for controlling foodborne diseases

Use of a lytic bacteriophage to control Salmonella Enteritidis in retail food

A Salmonella Enteritidis lytic bacteriophage designated as SE07 was isolated from retail meat samples. Electron micrograph revealed that phage SE07 belonged to family Podoviridae. Phage SE07 was relatively stable at the temperature ranging from 28 to 65 °C. Furthermore, it exhibited remarkable pH stability (between pH 4.0–11.0). The effectiveness of phage SE07 was determined in different food matrices (fruit juice, fresh eggs, beef and chicken meat) experimentally contaminated with S. Enteritidis. A significant reduction of S. Enteritidis population (about 2 log cycles) was obtained in fruit juice and fresh eggs after incubation at 4 °C for 48 h. Furthermore, within the same period, bacterial population was reduced by 2.1 and 2.0 log cycles on the bacteriophage treated beef and chicken meat samples, respectively. In this study, the obtained data suggested that phage SE07 might have potential uses against Salmonella food-borne infections

Isolation of food-borne pathogen bacteriophages from retail food and environmental sewage

Bacteriophages are the viruses of bacteria and are widely distributed in the biosphere, exhibiting dramatic manifestations both in liquid cultures and on solid media. In this study, bacteriophages were isolated from different types of food (beef, chicken meats, cucumber, lettuce, clam, cockles and shrimp) and sewage samples using 6 reference pathogen strains (Salmonella Enteritidis, Salmonella Typhimurium, Campylobacter jejuni, Vibrio parahaemolyticus, Listeria monocytogenes and Escherichia coli). A total of 29 bacteriophage isolates were obtained and further examined for titer via agar overlay assay. The titers were determined within the range of 108 to 1011 PFU/mL. Our results showed that diverse of bacteriophages are naturally present in a variety of foods

Development of a quantitative microbial risk assessment model for foodborne Campylobacter infection

Campylobacterspecies are one of the important foodborne pathogens in the world. Risk assessment is a scientific approach for estimating and evaluating potential adverse effects on human with resulting from exposure to hazards. A microbiological risk assessment was conducted to assess the health risk associated with consumption of chicken meat contaminated with Campylobacter in Malaysia. The risk assessment model was developed based on the framework proposed by the Codex Alimentarius Commission with simulating the contamination of chicken with Campylobacter from retail to table continuum. Available published data was incorporated into the model for estimation of the associated risk. The risk assessment model was created using @RISK software. Monte Carlo assessment was used to calculate the risk of Campylobateriosis associated with the consumption of chicken. According to the simulation analysis, the probability of contamination of chicken with Campylobacter spp. was 82.29 %. The model predicted that risk of illness due to undercooked chicken was 94.40 per 100, 000 population per year. Findings of this study will aid to identify the appropriate effective risk mitigation strategies in eliminating Campylobacter from poultry