Guidance on validation of lethal control measures for foodborne pathogens in foods

Giardia duodenalis, Cryptosporidium spp. and Toxoplasma gondii are protozoan parasites that have been highlighted as emerging foodborne pathogens by the Food and Agriculture Organization of the United Nations and the World Health Organization. According to the European Food Safety Authority, 4786 foodborne and waterborne outbreaks were reported in Europe in 2016, of which 0.4% were attributed to parasites including Cryptosporidium, Giardia and Trichinella. Until 2016, no standardized methods were available to detect Giardia, Cryptosporidium and Toxoplasma (oo)cysts in food. Therefore, no regulation exists regarding these biohazards. Nevertheless, considering their low infective dose, ingestion of foodstuffs contaminated by low quantities of these three parasites can lead to human infection. To evaluate the risk of protozoan parasites in food, efforts must be made towards exposure assessment to estimate the contamination along the food chain, from raw products to consumers. This requires determining: (i) the occurrence of infective protozoan (oo)cysts in foods, and (ii) the efficacy of control measures to eliminate this contamination. In order to conduct such assessments, methods for identification of viable (i.e. live) and infective parasites are required. This review describes the methods currently available to evaluate infectivity and viability of G. duodenalis cysts, Cryptosporidium spp. and T. gondii oocysts, and their potential for application in exposure assessment to determine the presence of the infective protozoa and/or to characterize the efficacy of control measures. Advantages and limits of each method are highlighted and an analytical strategy is proposed to assess exposure to these protozoa.

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Frequency and Antimicrobial Resistance of Salmonella Serotypes on Beef Carcasses at Small Abattoirs in Jalisco State, Mexico

Journal of Food Protection ◽

10.4315/0362-028x.jfp-11-423 ◽

2012 ◽

Vol 75 (5) ◽

pp. 867-873 ◽

Cited By ~ 12

Author(s):

JULIA A. PEREZ-MONTAÑO ◽

DELIA GONZALEZ-AGUILAR ◽

JEANNETTE BARBA ◽

CARLOS PACHECO-GALLARDO ◽

CARLOS A. CAMPOS-BRAVO ◽

...

Keyword(s):

Antimicrobial Resistance ◽

Salmonella Typhimurium ◽

Foodborne Pathogens ◽

Multidrug Resistant ◽

Control Measures ◽

Wet Season ◽

Beef Carcasses ◽

Salmonella Serotypes ◽

Group B ◽

Inspection Service

The prevalence and antimicrobial resistance of Salmonella serotypes on beef carcasses from four small abattoirs in Jalisco State, Mexico, were investigated during a 10-month period. Following U.S. Department of Agriculture Food Safety and Inspection Service protocols, Salmonella was isolated from 78 (15.4%) beef carcasses (n = 505) after the final carcass water wash. Isolation frequency differed by establishment (P < 0.05) and was higher (P < 0.05) during the wet season (May through September) for all establishments. Thirteen Salmonella serotypes and four serogroups (partially serotyped isolates) were identified. The most prevalent were Salmonella enterica Give (24.4%), Salmonella Typhimurium (17.9%), and Salmonella Group B (14.1%). Antimicrobial susceptibility was tested against 11 drugs, and results indicated that 46.2% of the isolates were resistant to tetracycline, 42.3% were resistant to streptomycin, 23.1% were resistant to chloramphenicol, 21.8% were resistant to trimethoprim-sulfamethoxazole, and 19.2% were resistant to gentamicin. No resistance to ceftriaxone or ciprofloxacin was observed, and 33% of the isolates were resistant to three or more antimicrobials. Although Salmonella Give was the most prevalent serotype, 95% of the isolates of this serotype were susceptible to all antimicrobials tested. Antimicrobial resistance was more common in Salmonella Typhimurium, and 93% (13 of 14) of the isolates of this serotype were resistant to at least five antimicrobials. The frequency of multidrug-resistant Salmonella isolates differed among establishments (P < 0.05) and may be related to the origin of the cattle presented for harvesting. These findings highlight the need for control measures to reduce Salmonella prevalence on beef carcasses in small abattoirs in Mexico and for strategies to ensure the cautious use of antimicrobials in animal production to prevent and control the spread of antimicrobial-resistant foodborne pathogens.

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Prevalence and molecular characterization of Shiga toxin-producing escherichia coli isolates from human and sheep in Al-Madinah Al-Munawarah

Infectio ◽

10.22354/in.v21i2.651 ◽

2017 ◽

Vol 21 (2) ◽

Author(s):

Eman Fathi Sharafa ◽

Iman I. Shabanaa

Keyword(s):

Escherichia Coli ◽

Foodborne Pathogens ◽

Shiga Toxin ◽

Genetic Relatedness ◽

Control Measures ◽

Health Concern ◽

Global Public Health ◽

E Coli ◽

Life Threatening

Shiga toxin-producing Escherichia coli (STEC) strains have emerged as important foodborne pathogens of global public health concern, causing life-threatening diseases. Sheep and their products have been documented as important reservoirs for STECs, especially E. coli O157. The aim of this study was to investigate STECs from diarrheal human and sheep in Al-Madinah Al-Munawarah, Saudi Arabia. Fecal samples were collected between June and August, 2015 from diarrheal humans (n = 134) and sheep (n = 87). Presumptive E. coli human-and sheep-isolated strains were identified for their serotypes, the associated virulence genes (Shiga toxin [stx1 , stx2 ], haemolysin [ehxA] and intimin [eae]) by polymerase chain reaction and their susceptibility to antibiotics. Pulsed-field gel electrophoresis (PFGE) was used to demonstrate the genetic relatedness between Serotype O157:H7 human- and sheep-isolated strains. Forty eight (48/221; 21.7%) STECs were recovered from both human and sheep, their serotypes were as follows: O157:H7, O26:H11, O157:HNM, O26:HNM, O128:H2, O48:HNM, O111:HNM and OUT:HUT. Various virulence profiles and multiple antibiotic resistance were observed among the isolates. Twenty eight O157:H7 serotypes (17 human isolates and 11 sheep isolates) were identified in 13 PFGE pulsotypes, where human and sheep isolates were highly related. PFGE banding profiles together with serotypes and genotypes afford proof that human and sheep can be colonized and infected with similar E. coli O157:H7 strains. Our findings highlight the importance of epidemiological and microbiological surveillance of STECs; as well as the development of control measures to decrease risks associated with zoonotic O157:H7.

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Prevalence, antimicrobial susceptibility pattern, and associated factors of Salmonella and Shigella among food handlers in Adigrat University student’s cafeteria, Northern Ethiopia, 2018

10.21203/rs.2.22938/v4 ◽

2020 ◽

Author(s):

Haftom Legese ◽

Tsega Kahsay ◽

Aderajew Gebrewahd ◽

Brhane Berhe ◽

Berhane Fseha ◽

...

Keyword(s):

Foodborne Pathogens ◽

Antimicrobial Susceptibility ◽

Associated Factors ◽

Public Health Problem ◽

Hand Washing ◽

Control Measures ◽

Major Public Health Problem ◽

Northern Ethiopia ◽

Food Handlers ◽

Cross Sectional

Abstract Background: Food handlers play a significant role in the transmission of foodborne infections. Salmonella and Shigella are the most common foodborne pathogens and their infections are a major public health problem globally. Thus, this study aimed to determine the prevalence, antimicrobial susceptibility patterns, and associated factors of Salmonella and Shigella among food handlers.Methodology: A cross-sectional study was conducted from March to August 2018 at Adigrat University student cafeteria, Northern Ethiopia. Data on socio-demographic and associated factors were collected using a structured questionnaire. Fresh stool samples were collected from 301 food handlers and transported to Adigrat University Microbiology Laboratory. Bacterial isolation and antimicrobial susceptibility test were performed using standard bacteriological methods. Data analysis was performed using SPSS version 22 and P < 0.05 with a corresponding 95% confidence interval was considered statistically significant.Results: A total of 301 food handlers were included in this study. The majority of study participants were females 265 (88.0 %). About 22 (7.3%) and 11 (3.7%) of food handlers were found to be positive for Salmonella and Shigella respectively. Hand washing after using a bathroom with water only, hand washing after using the bathroom, hand washing after touching dirty materials, hand washing before food handling, and fingernails status were significant associated factors identified. None of the Salmonella and Shigella isolates were sensitive to ampicillin. On the other hand, low resistance was found for chloramphenicol, ceftriaxone, and ciprofloxacin.Conclusion: The present study revealed that the prevalence of Salmonella and Shigella among food handlers was 22 (7.3%) and 11 (3.7%) respectively. Such colonized food handlers can contaminate food, drinks and could serve as a source of infection to consumers via the food chain. This indicates that there is a need for strengthened infection control measures to prevent Salmonella and Shigella transmission in the students’ cafeteria.

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Prevalence, antimicrobial susceptibility pattern, and associated factors of Salmonella and Shigella among food handlers in Adigrat University student’s cafeteria, Northern Ethiopia, 2018

10.21203/rs.2.22938/v6 ◽

2020 ◽

Author(s):

Haftom Legese ◽

Tsega Kahsay ◽

Aderajew Gebrewahd ◽

Brhane Berhe ◽

Berhane Fseha ◽

...

Keyword(s):

Foodborne Pathogens ◽

Antimicrobial Susceptibility ◽

Associated Factors ◽

Public Health Problem ◽

Hand Washing ◽

Control Measures ◽

Major Public Health Problem ◽

Northern Ethiopia ◽

Food Handlers ◽

Cross Sectional

Abstract Background: Food handlers play a significant role in the transmission of foodborne infections. Salmonella and Shigella are the most common foodborne pathogens and their infections are a major public health problem globally. Thus, this study aimed to determine the prevalence, antimicrobial susceptibility patterns, and associated factors of Salmonella and Shigella colonization among food handlers.Methodology: A cross-sectional study was conducted from March to August 2018 at Adigrat University student cafeteria, Northern Ethiopia. Data on socio-demographic and associated factors were collected using a structured questionnaire. Fresh stool samples were collected from 301 food handlers and transported to Adigrat University Microbiology Laboratory. Bacterial isolation and antimicrobial susceptibility test were performed using standard bacteriological methods. Data analysis was performed using SPSS version 22 and P < 0.05 where a corresponding 95% confidence interval was considered statistically significant.Results: A total of 301 food handlers were included in this study. The majority of study participants were females 265 (88.0 %). About 22 (7.3%) and 11 (3.7%) of food handlers were found to be positive for Salmonella and Shigella respectively. Hand washing after using a bathroom with water only, no hand washing after using the bathroom, no hand washing after touching dirty materials, no hand washing before food handling, and untrimmed fingernails were significant associated factors identified. None of the Salmonella and Shigella isolates were sensitive to ampicillin, yet low resistance against chloramphenicol, ceftriaxone, and ciprofloxacin was found. Conclusion: The present study revealed that the prevalence of Salmonella and Shigella among food handlers was 22 (7.3%) and 11 (3.7%) respectively. Such colonized food handlers can contaminate food, and drinks and could serve as a source of infection to consumers. This indicates that there is a need for strengthened infection control measures to prevent Salmonella and Shigella transmission in the students’ cafeteria.

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Dead or alive? Comparing costs and benefits of lethal and non-lethal human–wildlife conflict mitigation on livestock farms

Oryx ◽

10.1017/s0030605313001610 ◽

2014 ◽

Vol 49 (4) ◽

pp. 687-695 ◽

Cited By ~ 74

Author(s):

J. S. McManus ◽

A. J. Dickman ◽

D. Gaynor ◽

B. H. Smuts ◽

D. W. Macdonald

Keyword(s):

Control Measures ◽

First Year ◽

Costs And Benefits ◽

Lethal Control ◽

Wildlife Conflict ◽

The Mean ◽

Livestock Farms ◽

Mean Cost ◽

Human Wildlife Conflict ◽

Conflict Mitigation

AbstractLivestock depredation has implications for conservation and agronomy; it can be costly for farmers and can prompt retaliatory killing of carnivores. Lethal control measures are readily available and are reportedly perceived to be cheaper, more practical and more effective than non-lethal methods. However, the costs and efficacy of lethal vs non-lethal approaches have rarely been compared formally. We conducted a 3-year study on 11 South African livestock farms, examining costs and benefits of lethal and non-lethal conflict mitigation methods. Farmers used existing lethal control in the first year and switched to guardian animals (dogs Canis familiaris and alpacas Lama pacos) or livestock protection collars for the following 2 years. During the first year the mean cost of livestock protection was USD 3.30 per head of stock and the mean cost of depredation was USD 20.11 per head of stock. In the first year of non-lethal control the combined implementation and running costs were similar to those of lethal control (USD 3.08 per head). However, the mean cost of depredation decreased by 69.3%, to USD 6.52 per head. In the second year of non-lethal control the running costs (USD 0.43 per head) were significantly lower than in previous years and depredation costs decreased further, to USD 5.49 per head. Our results suggest that non-lethal methods of human–wildlife conflict mitigation can reduce depredation and can be economically advantageous compared to lethal methods of predator control.

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Pre-Harvest Survival and Post-Harvest Chlorine Tolerance of Enterohemorrhagic Escherichia coli on Lettuce

Toxins ◽

10.3390/toxins11110675 ◽

2019 ◽

Vol 11 (11) ◽

pp. 675 ◽

Cited By ~ 1

Author(s):

Deepti Tyagi ◽

Autumn L. Kraft ◽

Sara Levadney Smith ◽

Sherry E. Roof ◽

Julie S. Sherwood ◽

...

Keyword(s):

Escherichia Coli ◽

Relative Humidity ◽

Foodborne Pathogens ◽

Enterohemorrhagic Escherichia Coli ◽

Control Measures ◽

Post Inoculation ◽

Sodium Hypochlorite Solution ◽

Post Harvest ◽

Salinas Valley ◽

The Impact

In the field, foodborne pathogens such as enterohemorrhagic Escherichia coli (EHEC) are capable of surviving on produce over time, yet little is known about how these pathogens adapt to this environment. To assess the impact of pre-harvest environmental conditions on EHEC survival, we quantified survival on romaine lettuce under two relative humidity (75% and 45%) and seasonal conditions (March and June). Greenhouse-grown lettuce was spray-inoculated with EHEC and placed in a growth chamber, mimicking conditions typical for June and March in Salinas Valley, California. Bacteria were enumerated on days 0, 1, 3, and 5 post-inoculation. Overall, we found that the effect of relative humidity on EHEC survival depended on the seasonal conditions. Under June seasonal conditions, higher relative humidity led to lower survival, and lower relative humidity led to greater survival, five days post-inoculation. Under March seasonal conditions, the impact of relative humidity on EHEC survival was minimal over the five days. The bacteria were also tested for their ability to survive a chlorine decontamination wash. Inoculated lettuce was incubated under the June 75% relative humidity conditions and then washed with a 50 ppm sodium hypochlorite solution (40 ppm free chlorine). When incubated under June seasonal conditions for three to five days, EHEC strains showed increased tolerance to chlorine (adj. p < 0.05) compared to chlorine tolerance upon inoculation onto lettuce. This indicated that longer incubation on lettuce led to greater EHEC survival upon exposure to chlorine. Subsequent transcriptome analysis identified the upregulation of osmotic and oxidative stress response genes by EHEC after three and five days of incubation on pre-harvest lettuce. Assessing the physiological changes in EHEC that occur during association with pre-harvest lettuce is important for understanding how changing tolerance to post-harvest control measures may occur.

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Survey of the U.S. Broiler Industry Regarding Pre- and Postharvest Interventions Targeted To Mitigate Campylobacter Contamination on Broiler Chicken Products

Journal of Food Protection ◽

10.4315/jfp-19-527 ◽

2020 ◽

Vol 83 (7) ◽

pp. 1137-1148 ◽

Cited By ~ 1

Author(s):

HAEJIN HWANG ◽

RANDALL S. SINGER

Keyword(s):

Foodborne Pathogens ◽

Broiler Chickens ◽

The United States ◽

Control Measures ◽

Processing Plant ◽

Broiler Industry ◽

Key Stakeholders ◽

Inspection Service ◽

Campylobacter Infection ◽

The U.S

ABSTRACT Campylobacter is one of the most commonly reported foodborne pathogens in the United States. Because poultry is considered a major source of Campylobacter infections in humans, reduction of Campylobacter contamination in poultry products is likely the most important and effective public health strategy for reducing the burden of campylobacteriosis in humans. A comprehensive on-line survey was conducted of key stakeholders in the U.S. broiler industry, including broiler farm managers (n = 18), poultry veterinarians (n = 18), and processing plant managers (n = 20), to assess the current pre- and postharvest Campylobacter interventions and control measures practiced by the industry for reducing Campylobacter contamination of broiler products. The survey also included information regarding each respondent's understanding of Campylobacter transmission and ecology in relation to broiler production. The results revealed that a majority of the establishments included in the survey are following the U.S. Department of Agriculture, Food Safety and Inspection Service guidelines for controlling Campylobacter contamination in broiler flocks and on carcasses. However, establishments appeared to be putting more effort into Salmonella control than into Campylobacter control both on the farm and in the processing plant. A majority of the respondents responded that current interventions are not effective for reducing Campylobacter contamination, especially on the farm. Many respondents did not understand the risk factors associated with Campylobacter colonization in broiler flocks and on carcasses. Continued educational and training programs for key stakeholders in the U.S. broiler industry are needed to increase awareness of the issues associated with Campylobacter infection in broiler chickens and of the fact that Campylobacter infection is a multifaceted problem that requires efforts from both the pre- and postharvest sectors. HIGHLIGHTS

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Low–Water Activity Foods: Increased Concern as Vehicles of Foodborne Pathogens

Journal of Food Protection ◽

10.4315/0362-028x.jfp-12-211 ◽

2013 ◽

Vol 76 (1) ◽

pp. 150-172 ◽

Cited By ~ 196

Author(s):

LARRY R. BEUCHAT ◽

EVANGELIA KOMITOPOULOU ◽

HARRY BECKERS ◽

ROY P. BETTS ◽

FRANÇOIS BOURDICHON ◽

...

Keyword(s):

Water Activity ◽

Foodborne Pathogens ◽

Food Processing ◽

Foodborne Illness ◽

Control Measures ◽

Food Category ◽

Food Ingredients ◽

Safety Risks ◽

Efficient Control ◽

Dry Food

Foods and food ingredients with low water activity (aw) have been implicated with increased frequency in recent years as vehicles for pathogens that have caused outbreaks of illnesses. Some of these foodborne pathogens can survive for several months, even years, in low-aw foods and in dry food processing and preparation environments. Foodborne pathogens in low-aw foods often exhibit an increased tolerance to heat and other treatments that are lethal to cells in high-aw environments. It is virtually impossible to eliminate these pathogens in many dry foods or dry food ingredients without impairing organoleptic quality. Control measures should therefore focus on preventing contamination, which is often a much greater challenge than designing efficient control measures for high-aw foods. The most efficient approaches to prevent contamination are based on hygienic design, zoning, and implementation of efficient cleaning and sanitation procedures in the food processing environment. Methodologies to improve the sensitivity and speed of assays to resuscitate desiccated cells of foodborne pathogens and to detect them when present in dry foods in very low numbers should be developed. The goal should be to advance our knowledge of the behavior of foodborne pathogens in low-aw foods and food ingredients, with the ultimate aim of developing and implementing interventions that will reduce foodborne illness associated with this food category. Presented here are some observations on survival and persistence of foodborne pathogens in low-aw foods, selected outbreaks of illnesses associated with consumption of these foods, and approaches to minimize safety risks.

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Prevalence, antimicrobial susceptibility pattern, and associated factors of Salmonella and Shigella among food handlers in Adigrat University student’s cafeteria, Northern Ethiopia, 2018

10.21203/rs.2.22938/v2 ◽

2020 ◽

Author(s):

Haftom Legese ◽

Tsega Kahsay ◽

Aderajew Gebrewahd ◽

Brhane Berhe ◽

Berhane Fseha ◽

...

Keyword(s):

Foodborne Pathogens ◽

Antimicrobial Susceptibility ◽

Associated Factors ◽

Public Health Problem ◽

Hand Washing ◽

Control Measures ◽

Major Public Health Problem ◽

Northern Ethiopia ◽

Food Handlers ◽

Cross Sectional

Abstract Background: Food handlers play a significant role in the transmission of foodborne infection. Salmonella and Shigella are the most common foodborne pathogens and their infections are a major public health problem of the globe. Thus, this study was aimed to determine the prevalence, antimicrobial susceptibility patterns, and associated factors of Salmonella and Shigella among food handlers. Methodology: A cross-sectional study was conducted from March to August 2018 at Adigrat University student cafeteria, Northern Ethiopia. Data on socio-demographic and associated factors were collected using a structured questionnaire. Fresh stool samples were collected from 301 food handlers and transported to Adigrat University Microbiology Laboratory. Bacterial isolation and antimicrobial susceptibility test were performed using standard bacteriological methods. Data analysis was performed using SPSS version 22 and P < 0.05 with a corresponding 95% confidence interval was considered statistically significant. Results: A total of 301 food handlers were included in this study. The majority of study participants were females 265 (88.0 %). About 22 (7.3%) and 11 (3.7%) of food handlers were found to be positive for Salmonella and Shigella respectively. Hand washing after using a bathroom with water only, hand washing after using the bathroom, hand washing after touching dirty materials, hand washing before food handling and fingernails status were significant associated factors identified. None of the Salmonella and Shigella isolates was sensitive to ampicillin. On the other hand, low resistance was found for chloramphenicol, ceftriaxone, and ciprofloxacin. Conclusion: The present study revealed that the prevalence of Salmonella and Shigella among food handlers found to be 22 (7.3%) and 11 (3.7%) respectively. Such colonized food handlers can contaminate food, drinks and could serve as a source of infection to consumers via the food chain. This indicates that the need for strengthened infection control measures to prevent Salmonella and Shigella transmission in the students’ cafeteria.

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